Introduction
In the spirit of a real-world philosophy approach,Footnote 1 this chapter explores the reality (in as much as it can) of the law relating to partial excuse in practice, taking the example of the defence of diminished responsibility as the proposed progenitor of the Universal Partial Defence (UPD). The operation of the defence is an important place to start when taking a more particularised theoretical approach to understanding the conception of partial excuse, and in seeking to legitimise its expansion to include social circumstance as well as a broader understanding of rational agency, as discussed in Chapter 7. Drawing on case law and empirical studies, the chapter presents a fine-grained account of the operation of the defence, showing how the court at times takes a penumbral stance on the meaning of ‘abnormality’ or ‘mental disorder’ for the purposes of diminished responsibility, in order to meet the perceived requirements of justice in a particular case. The analysis also sheds light on the remit of the expert and the role of the jury in evaluating the defendant’s moral blameworthiness, with a view to reinforcing the primacy of the normative test upon which the defence is based. Finally, the chapter consolidates what is salvageable from the defence to transition towards the UPD. Before embarking on the greater analysis, however, the chapter outlines the reasons for using diminished responsibility as a template for the UPD and why, though valuable as a basis for the proposal, the defence ought to be handled with caution.
A Template for the UPD
Scholars who recommend the introduction of a generic partial excuse at the pre-verdict stage tend to base their recommendations on the existing US Model Penal Code definition of the insanity defence and that of ‘extreme (mental and) emotional disturbance’ (EMED/EED).Footnote 2 For instance, Morse favours a definition that might look something like the EMED formula: ‘extreme mental or emotional disturbance for which there is reasonable explanation or excuse’.Footnote 3 And though his approach is largely endorsed by scholars such as Coppola and Lambert,Footnote 4 it is worth noting his viewpoint in making this recommendation to the effect that he did not designate the words of the test itself as crucial. Rather, he opines that ‘[j]uries just need some formulation roughly to guide their normative judgment’.Footnote 5 While the adoption of some version of the Model Penal Code wording might appear plausible from the US perspective, however, it is likely to be less favourable to the jurisdictions of the UK and Ireland. For, in its consideration of the EMED defence during its review of the law of provocation, the Law Commission of England and Wales rejected the EMED definition on account of its perceived vagueness.Footnote 6 Therefore, it is the position of this book that though much can be gained from the MPC definitions, the arrangement of diminished responsibility under the Coroners and Justice Act 2009 offers a more feasible starting point for the UPD, given its more concrete structure which provides a clearer division between the grounds of an excuse and the excusing condition itself. In this vein, the UPD sits closer to Paul Robinson’s more recent proposal for a ‘general mitigation provision’ which recognises both situational and capacity-based grounds as potential excusing conditions, and explicitly imbeds a normative inquiry into the proposed defence.Footnote 7 However, as discussed in Chapter 8, the blueprint is offered with knowledge of the fact that different jurisdictions will have divergent normative preferences as well as process and evidential requirements, which will impact definitional approaches.
Moreover, diminished responsibility is deemed favourable to loss of control or provocation as the basis of the UPD because it has the farther reach of the partial defences. Diminished responsibility at present includes impairment of both rational and cognitive capacities, and its basis is not necessarily related to the actions of other parties. Provocation/loss of control, on the other hand, has a very particular origin and complex rationale,Footnote 8 owing to its focus on the actions of the victim, and its categorisation as either partial justification or partial excuse.Footnote 9 Therefore, depending on how it is defined, provocation/loss of control may be included or excluded within the UPD, as addressed in more detail in Chapter 8. Accordingly, this form of partial excuse is not central to my argument in this chapter. Finally, drawing from the approach and terminology of the doctrine of diminished responsibility in its present form also provides a useful gauge for the court’s potential reception of a UPD in practice.
It is worth noting, however, that though diminished responsibility serves as a valuable reference point for the UPD, it is insufficient in its current mode to meet the requirements of the Real Person Approach (RPA) as described in Part II. Even if the defence was to be applied to all offence categories in its present form, its scope is problematic because it is restricted to biological and psychological conditions and does not (formally, at least) permit the consideration of emotional and/or social circumstances in impeding responsibility. This stance stymies the advancement of the RPA at culpability evaluation because it fails to recognise the impact of social factors on individual behaviour. In addition, the basis of the diminished responsibility doctrine is largely framed in terms of ‘abnormality’ of mind or mental functioning; in other words, that there must be something ‘far wrong’ with somebody to avail of the defence.Footnote 10 While there is a need to differentiate defendants who can bring a defence from those who cannot,Footnote 11 the categorisation of the former group as ‘abnormal’ is both damaging and limiting, and falls foul of the understanding of universality afforded to the defence as outlined in Chapter 5.
The juxtaposition of the concept of abnormality with that of normality is deeply engrained in the criminal law.Footnote 12 As such, abnormality is a legal construct and its interpretation can be capricious in nature, changing across time in response to emerging scientific knowledge and social sensibilities. As Norrie opines: ‘[W]hat is abnormal depends upon social perception, and therefore upon a socio-political label being stuck upon it.’Footnote 13 Though not given a scientific definition in law, a classification of abnormality still supports a medical model of labelling that locates the source of the mental illness within the psyche of the individual,Footnote 14 which can lead to stigmatisation, discrimination, and increased likelihood of negative outcomes for the person concerned.Footnote 15 One damaging effect in a legal context may be demonstrated by potentially deserving defendants failing to avail of defences like insanity and diminished responsibility owing to their rejection of the medical model, underpinned by a fear of stigmatisation. For example, there is evidence that some female defendants who were victims of abuse avoid pleading diminished responsibility as they feel that they have had a normal response to an abnormal and traumatic situation.Footnote 16 The abnormality categorisation is also limiting in the sense that there is a hesitancy to bring within the remit of the defence other factors that impede capacity but are perceived of as ‘normal’ in nature. For example, defendants that may have developmental immaturity, as discussed later, are excluded from bringing a diminished responsibility defence because the condition is classed as ‘normal’ and so does not align with the notion of abnormality in the legislation. The position endures notwithstanding the fact that it is uncontroversial to assert that developmental immaturity impairs volitional capacity.Footnote 17 As such, the medicalised construct of diminished responsibility in its present form is at odds with the normalising conception of differentiation inherent in the RPA, and which is exhibited by the more neutral wording of the UPD as outlined in Chapter 8.
The Diminished Responsibility Defence
The diminished responsibility defence has long endured heavy criticism on account of its ambiguous nature.Footnote 18 Attempts at clarity and modernisation have focused on the further medicalisation of the doctrine,Footnote 19 and a tightening of the causal link between the defendant’s condition and the offence.Footnote 20 Conversely, arguments for its expansion have met with concerns about ‘an evaluative free for all’.Footnote 21 This section argues that with such ambiguity comes a flexibility of interpretation that has remained constant in practice notwithstanding the reinforcement of the medical model in statute. Thus, for the most part, the behaviour of the court indicates a commitment to the normative origins of the defence and the need to recognise all relevant factors, not just psychiatric, that impact on a defendant’s culpability for the purposes of partial exculpation. This approach finds support in Timothy Endicott’s critique of precision in law. Endicott argues that while setting clear proscriptions might appear appropriate, like a speed limit for driving offences which may be beneficial for the purposes of a deterrence rationale, for example this logic may not suit all cases.Footnote 22 Thus, in more complex normative assessments, Endicott suggests that less precision can mean a more appropriate response, for example, where a vague standard can work to assign the function of resolving a particular issue to a more appropriate entity.Footnote 23 As such, it is arguable that the jury (or judge) is the most appropriate arbiter of community norms in cases involving more complex questions of culpability determination, as envisaged by diminished responsibility and, indeed, the UPD. With this in mind, let’s examine more closely the standard terminology and what it might mean for the proposed reform.
Abnormality of Mind/Mental Functioning
Definitions of the diminished responsibility defence employ psychologically orientated wording that – either explicitly or implicitly – places the presence of a diagnosable mental condition at the time of the wrongful act at the core of whether the defendant is entitled to a finding of reduced culpability. For example, the partial defence in the Scottish jurisdiction has retained the common law term ‘abnormality of mind’ under the 2010 Act,Footnote 24 Northern Ireland and England and Wales employ the term ‘abnormality of mental functioning’,Footnote 25 and in the Irish jurisdiction, the 2006 Act requires evidence of a ‘mental disorder’ at the time of the crime.Footnote 26
Though generally non-prescriptive in legislation, the interpretation of abnormality tends to rely heavily on an expert psychiatrist to give evidence of a formal diagnosis. The level of reliance on a medical model in this context varies across the relevant jurisdictions, ranging from England and Wales and Northern Ireland as the most medicalised version, followed closely by Ireland, to Scotland as the least medicalised. The 2009 Act in England and Wales replaced ‘abnormality of mind’ with ‘abnormality of mental functioning’, reflecting the desire for a more ‘medically precise’ plea in order to cater to the requirements of psychiatric experts,Footnote 27 and to ‘standardise the application of the test’.Footnote 28 There was a perception amongst scholars that this development would lead to a narrowing of the defence;Footnote 29 however, Mackay’s empirical work suggests that this predication is not a certainty.Footnote 30 Though his more recent examination of CPS files indicates an increase in murder convictions, the reason for this is more likely to do with the fact that more cases are going before the jury.Footnote 31 As such, there is some doubt about the extent to which the medicalisation of the defence has materialised in practice, particularly given that the hinge upon which the abnormality is evaluated remains normative.
Though reliant on scientific validation, the state of mind of the defendant at the time of the defence is ultimately a matter of law and not expert opinion.Footnote 32 Across the jurisdictions, the abnormality is largely based on the defendant’s volitional and/or cognitive capacity.Footnote 33 In England and Wales, abnormality of mental functioning relates to three specified abilities under the 2009 Act; the defendant’s capacity to understand, to judge, and to control their actions.Footnote 34 Notwithstanding the turn towards the medicalisation of the defence in this jurisdiction, very little has been said about these abilities, prompting Mackay to contemplate ‘whether the impairment factors in the new s. 2 are psychiatric in the manner which is clearly the case for “recognised medical condition”’.Footnote 35 These abilities remain informed by the common law, and in particular, the case of R. v. Byrne,Footnote 36 where Lord Parker CJ said that ‘abnormality of mind’ was considerably wider than the concept of ‘defect of reason’ under the M’Naghten Rules. He went on to hold that the term was:
wide enough to cover the mind’s activities in all its aspects, not only the perception of physical acts and matters, and the ability to form a rational judgement as to whether an act is right or wrong, but also the ability to exercise will-power to control his physical acts in accordance with that rational judgment.Footnote 37
Though Lord Parker’s words clearly form the basis of the new legislative abilities (albeit with the omission of the reference to ‘whether an act is right or wrong’), case law suggests that they should be read with the ‘psychiatric tenor of the whole section’ in mind, including in relation to the expert giving an opinion on the ultimate issue.Footnote 38 However, as psychiatrists themselves attest, there is no consensus on the meaning ‘abnormality of mental functioning’ in psychiatric practice.Footnote 39 Indeed, Nathan goes so far as to recommend that ‘caution should be exercised in offering evidence on the presence of an issue for which there is not an agreed clinical definition’.Footnote 40 He further advises that experts adopt an understanding of the term ‘mental state’, as the nearest psychiatric equivalent to ‘abnormality of mental functioning’, when considering whether or not the defendant’s state of mind was disturbed, and disturbed for the purposes of amounting to abnormality of mental functioning under the 2009 Act.Footnote 41
Looking more closely at the three abilities (to understand, to judge, and to control actions) suggests a stronger normative, rather than medical, underpinning to the law which has not changed to any great degree since the new legislation. For example, the first limb, ‘understanding the nature of D’s conduct’, continues to garner confusion.Footnote 42 Hallett and Mackay both point to its similarity to the insanity defence under M’Naghten, and suggest it is akin to the defendant’s ability to appreciate the nature and quality of the act. It has a moral property that Hallett suggests supports its consideration as a matter for the jury.Footnote 43 His point is bolstered by the fact that Mackay and Mitchell’s study suggests that experts tend to avoid using this limb in giving an opinion on abnormality. For example, the authors found that the ability to understand one’s conduct was the least commonly referenced in expert reports reviewed, at 41.8 per cent, and there were no cases where this limb was cited as the basis of an abnormality by itself.Footnote 44
Forming a rational judgement was the most frequently cited ability in Mackay and Mitchell’s study, at 78.2 per cent of reports.Footnote 45 As a result, this particular capacity is of significance to psychiatrists when considering the impact of the abnormality on the defendant’s conduct.Footnote 46 Yet the notion of rationality falls outside psychiatric nosology,Footnote 47 as the Law Commission alludes to with the following statement: ‘[t]he capacity to be rational needs to be understood as encompassing all that goes on in the mind, incorporating the interplay between the abilities to think, to believe and to experience feelings’.Footnote 48 Some commentators would go further, arguing that rationality is best categorised as a cultural, and therefore normative, concept as opposed to purely scientific.Footnote 49 Case law has also emphasised that the question of rationality is inherently a moral one.Footnote 50
The third limb, the ability to exercise self-control, was referenced by 70 per cent of the expert reports in Mackay and Mitchell’s study.Footnote 51 This concept was also elucidated in the decision in Byrne, as set out previously.Footnote 52 The primary issue with the Byrne criteria which section 52 fails to clarify, however, is the ‘irresistible impulse’ element, in that the difficulties and uncertainties which deterred judges from allowing the irresistible impulse defence under the M’Naghten Rules in the first place, still remain.Footnote 53 As Lord Parker C. J. opined:
[T]he step between ‘he did not resist his impulse’ and ‘he could not resist his impulse’ is … one which is incapable of scientific proof … there is no scientific measurement of the degree of difficulty which an abnormal person finds in controlling his impulses.Footnote 54
The point has been echoed more recently by the Law Commission and academic commentators,Footnote 55 with the result that, as Hallett remarks, ‘[i]f an impairment of self-control is difficult to prove scientifically, it is less of a psychiatric issue and more a question for the jury’.Footnote 56 The framing of volitional capacity as a normative question is further supported when we consider its role as part of the loss-of-control test which replaced provocation under section 54 of the 2009 Act. The interpretation of the concept of loss of control under section 54 entrusts the jury with the ability to recognise a lack of self-control, yet the interpretation of loss of control under section 52 of the same Act assumes the need for psychiatric testimony on the matter. Hallett makes the point that this duality of interpretation creates a ‘legal fiction’,Footnote 57 which potentially undermines the legitimacy of both tests. For, while psychiatric evidence may bear on educating a jury on whether or not a particular aspect of a disorder involves loss of self-control, if juries in a provocation case are trusted to recognise a defendant’s loss of control,Footnote 58 it supports the case that juries in a diminished responsibility case ought to be afforded the same trust. Of course, what distinguishes the two defences, as implied by the court in R. v. Rejmanski,Footnote 59 is the origin of the loss of control, emphasising the contradictions and confusions that emerge as a result of the law’s propensity to differentiate the normal from the abnormal.
The UPD Approach
The UPD values the role of assessing the capacity of the individual as central to maintaining alignment with the present dominant approach to determinations of culpability, as discussed in more detail in Chapter 7. In line with present reading of this part of the defence, the blueprint to follow in Chapter 8 fore-fronts the normative nature of such capacity assessment by emphasising its place as the excusing condition on which the defence pivots. Support for this position can be garnered from Morse’s proposal for a general partial excuse which targets individuals who have a mental disorder that does not meet the high bar set by the insanity defence, or is out with homicide, and so does not qualify for a partial defence (though he also acknowledges as an excusing condition nonculpable hard choice occasioned by threat of harm).Footnote 60 Morse’s core contribution for present purposes is his insistence on the central role of the excusing condition in determining the validity of criminal excuses, over and above appeals to more particularised syndromes or pathologies. His account of partial excuse seeks to avoid the pitfalls of the medical model of abnormality, and instead centres on the question of impaired rationality, allowing him to avoid the murkier territory of causation. He writes: ‘What the delusional defender and the child have in common is not “pathological causation”; they have in common the absence of full capacity for rationality. Irrationality is the genuine excusing condition that is operative.’Footnote 61
Morse’s excusing condition amounts to either compulsion (a conventional account of duress) or the absence (or reduction) of rational capacity which he characterises as ‘normative competence’: ‘rationality is required for responsibility, and nonculpable irrationality or lack of normative competence is an excusing condition.’Footnote 62 For Morse, though he acknowledges that the capacity for rationality is ‘a congeries of perceptual, cognitive, and affective abilities’, his overall construct of normative competence elevates impaired rational capacity as an excusing condition, above all others.Footnote 63 His explanation of rational capacity reveals support for a standard reasons-responsiveness account, as explored in further detail in Chapter 4, when he says: ‘[T]he agent has the normative competence to understand and to be guided by the reasons that support a moral prohibition that we accept.’Footnote 64 Notably, he does not endorse the idea of volition as an excusing condition in itself; rather, he argues that volitional control deficit is more likely to form part of the question around establishing intention, and that it also may be understood within the context of rational capacity deficit claims.Footnote 65 Morse also appears to frame impulsivity more as an unfortunate character trait than a basis for excuse.Footnote 66 Moreover, he alludes to the relevance of emotion ‘the ability to empathize and to feel guilt or some other reflexive reactive emotion’,Footnote 67 as an affective ability related to rational capacity. As such, Morse’s account is structurally helpful but too narrow in scope to meet the requirements of the RPA. This is reflected by the fact that though he recognises that his proposal has the potential to be used beyond mental disorder–type conditions, because of the emphasis on the normative excusing condition, he is generally reluctant for it to be used as a vehicle for wider structural claims, like a poverty-type defence.Footnote 68
Morse’s understanding of normative competence has been fleshed out in the literature, however. The work of Lambert showcases how the GPR may be deployed to facilitate situational factors that bear on culpability in her adaptation of Morse’s general partial excuse to accommodate a scarcity/poverty defence. Lambert explains how a scarcity mindset, or the ‘subjective experience of having less than you feel you need’,Footnote 69 impacts aspects of both cognitive capacity and executive control, and so her understanding of excusing conditions more explicitly includes both cognitive and volitional impairments.Footnote 70 In addition, Coppola’s understanding of normative competence is broader than Morse and Lambert in that it amounts to ‘the relevant mental capacities that are necessary for culpability’.Footnote 71 Coppola sheds light on the lack of attention afforded to the role of emotion in culpability determinations and argues that it has as much a place as cognition in guiding behaviour.Footnote 72 Thus, for Coppola, ‘the legal determination that an individual is mentally capable should also – and more accurately – rest on the individual’s capacity for emotionally understanding or appreciating the moral significance of his or her conduct’.Footnote 73 While Coppola admits the meaning of emotional appreciation is not always clear,Footnote 74 she puts forward a convincing argument for its inclusion as an excusing condition based on an extensive evaluation of scholarship on emotional capacity. In summary, Coppola’s definition of emotional capacity amounts to:
the capacity to care for the interests of other human beings, the capacity to engage in the moral evaluation of one’s self and experience moral emotions, such as guilt, shame, remorse, and resentment, the capacity to internalise the normative expectations of others, the capacity to respond to moral norms as a motivation for one’s conduct, and the capacity to self-identify with moral norms. Collectively, emotional capacity is mostly framed in moral terms as a capacity to feel the significance of moral norms (eg, to self-identify with moral norms and be vulnerable to feelings of shame, guilt, and remorse when failing to conform one’s conduct in accordance with them).Footnote 75
In light of the preceding discussion, the UPD also disavows the use of terms like ‘abnormality’ given their propensity to dehumanise and so to contribute to the pathogenic vulnerability of the accused. And while the UPD too accepts the centrality of the accused’s capacity as the basis of the excusing condition, the RPA demands that it embrace a broader understanding of that capacity that reflects a more authentic account of personhood, as developed in Chapter 2. In this regard, it would propose the retention of a term like ‘mental functioning’ but ensure that it is interpreted in a more generous way than the present doctrine, so as to include emotional, as well as cognitive and volitional, capacity, and to understand those capacities as interdependent.
The Basis of a Defence: A Medical Diagnosis?
A formal trend involving government and core stakeholders towards pathologising the defence is particularly evident in England and Wales and Northern Ireland, with the introduction of the ‘recognised medical condition’ requirement under the 2009 Act. Previously, the law of diminished responsibility under s. 2 of the 1957 Act specified conditions of ‘arrested or retarded development of mind or any inherent causes or induced by disease or injury’ as the basis of the ‘abnormality of mind’ requirement. The wording was essentially non-medical and was rarely remarked upon by the courts or by experts.Footnote 76 The somewhat loose interpretation of the wording by the courts was designated a ‘benign conspiracy’Footnote 77 which stretched the notion of ‘abnormality of mind’ to enable a verdict to meet the requirements of justice in the case.Footnote 78 Yet fears around the defence being ‘grossly abused,Footnote 79 accusations of ‘the smuggling in of mercy’,Footnote 80 and concerns about showing leniency to the ‘highly stressed killer’, in addition to broader criticisms concerning the wording of the defence,Footnote 81 led to the listed conditions being removed and replaced with the term ‘recognised medical condition’ under the 2009 Act. The Royal College of Psychiatrists supported this change, commenting that the introduction of such a restriction would ‘ensure that any such defence was grounded in valid medical diagnosis’ / ‘encourage reference within expert evidence to diagnosis in terms of one or two of the accepted international classificatory systems of mental conditions (WHO ICD10 and APA DSM) without explicitly writing those systems into the legislation’ / ‘avoid individual doctors offering idiosyncratic “diagnoses” as the basis for a plea of diminished responsibility’.Footnote 82 The shift towards medicalising the defence is further reinforced by subsequent case law, for instance, in R. v. Brennan where the Court of Appeal asserted that the criteria under the 2009 Act relates ‘entirely to psychiatric matters’.Footnote 83
Notwithstanding the endorsement by government and experts of a medical model of diminished responsibility, however, observations of the law in practice indicate a sustained flexibility in terms of the variety and nature of the conditions that have formed the basis of a successful defence in England and Wales. Mitchell’s 1997 study highlighted that the term ‘abnormality of mind’ under the 1957 Act was deemed broad enough to include conditions like neurotic disorders, premenstrual syndrome, sexual deviation, and battered spouse syndrome.Footnote 84 Mackay and Mitchell’s 2017 study,Footnote 85 perhaps unsurprisingly, shows that the most frequent primary diagnoses since the implementation of the 2009 Act are established mental disorders, namely schizophrenia, depression, personality disorder,Footnote 86 and psychosis.Footnote 87 However, it remains the case that other more controversial diagnoses or circumstances continue to be relied upon by defendants – for example, addiction, post-traumatic stress disorder, and mercy killing.
The defence in Ireland has a significantly shorter history than its neighbouring jurisdictions, as it did not have a common law antecedent prior to the introduction of the doctrine under the 2006 Act. It was introduced at a time when s. 2 in England and Wales was being criticised as overly broad which may have contributed to the more stringent intention underlying the notion of ‘mental disorder’ in the Irish definition, in addition to Ireland’s more conservative judicial approach. For example, referring to the 2002 Bill which led to the 2006 Act, the Law Reform Commission states that it is likely that psychopathy does not fall within the scope of section 6.Footnote 88 However, the Irish version still retains some potential for flexibility within the definition of ‘mental disorder’ given its reference to the common law concept of ‘disease of the mind’.Footnote 89 In practice, the court’s interpretation of ‘mental disorder’ under the 2006 Act has largely sustained a medicalised model, accepting conditions such as depersonalisation disorder, schizo-affective disorder, and dementia, though excluding personality disorder,Footnote 90 and alcoholism.Footnote 91
Scotland, where the doctrine originated, has bucked the trend towards medicalising the defence in recent years. Prior to the landmark case of Galbraith, it was assumed that diminished responsibility in Scotland depended upon a finding that the accused had a mental illness or disease, but this is no longer necessary,Footnote 92 with the result that the reach of the plea has been widened significantly.Footnote 93 However, it is worth noting that this stance ought to be viewed in light of the fact that the defence of provocation in this jurisdiction is restricted to violence or reasonable belief of violence on the part of the accused, in addition to sexual infidelity, with provocation by words alone not available in the context of a murder charge.Footnote 94 Immediacy remains a requirement, and so cases of cumulative provocation in Scotland are more likely to be dealt with via diminished responsibility, or subject to a more informal plea negotiation in the context of culpable homicide.Footnote 95 Though it is noteworthy that this position is presently under review by the Law Commission and is likely to change due to criticism pertaining to provocation in a domestic abuse context in particular.Footnote 96 At present, however, the restrictive nature of provocation suggests a greater requirement for a flexible diminished responsibility option. The Law Commission’s recommendations in respect of diminished responsibility were taken on board by the Scottish Executive and implemented by the Criminal Justice and Licensing (Scotland) Act 2010.Footnote 97 Section 168 inserts the following definition into section 51B of the Criminal Procedure (Scotland) Act 1995:
A person who would otherwise be convicted of murder is instead to be convicted of culpable homicide on grounds of diminished responsibility if the person’s ability to determine or control conduct for which the person would otherwise be convicted of murder was, at the time of the conduct, substantially impaired by reason of abnormality of mind.
The lack of medical terminology within the definition further suggests a broad approach.
In practice, the position in Scotland is the most flexible of the jurisdictions under review in terms of the conditions that amount to ‘abnormality of mind’. In Galbraith, the Court of Appeal conducted an extensive analysis of the nature of mental condition that is required in order to permit the defence,Footnote 98 and found that the following conditions have formed the basis of a defence since the case of Dingwall in 1867; sunstroke, epilepsy, delirium tremens, mental impairment, depression, endocrine disorders, side effects of medication, and also a recognised abnormality arising from sexual or other forms of abuse. It can be ‘congenital or derive from an organic condition, from some psychotic illness, such as schizophrenia or severe depression, or from the psychological effects of severe trauma’.Footnote 99 The Court went on to clarify that the condition must be recognised by the ‘appropriate science’, and expert evidence is not limited to those with a medical qualification; professions such as psychologists could also give evidence. The Court in McLeod v. H.M. Advocate also indicated that sexual abuse, physical abuse, and post-traumatic stress disorder can bring about mental abnormality. Crichton et al.’s study of successful diminished responsibility cases since Galbraith also points to more unexpected circumstances satisfying the mental condition element in Scotland, particularly: dependent personality disorder, battered person’s syndrome,Footnote 100 ‘significant emotional problems’, adjustment disorder following a cancer diagnosis, and an abnormal grief reaction. In addition, non-psychiatric factors were successful in one case where it was deemed that the defendant had not shown the ‘wicked recklessness’ necessary for murder. In respect of ‘psychopathic’ personality disorder, Crichton et al.’s study suggests that this condition will not be accepted unless the accused can show that an aspect of the condition may be understood in the context of past abuse.Footnote 101
Reflecting on these findings in tandem, we might expect to see established psychiatric diagnoses like schizophrenia and psychosis, for example, as forming an acceptable basis for the defence of diminished responsibility, particularly in light of the fact that it is informed by a capacity-based approach to excuse as the dominant theory of criminal responsibility,Footnote 102 as discussed in more detail in Chapter 7. In addition, owing to the psychologically orientated wording of the defence generally, it would seem to counter the intention of the various legislative definitions if conditions or circumstances extraneous to the psychology of the accused were to form the basis of a defence. However, as evidenced earlier, in practice there is a tendency to include conditions that have a penumbral quality, as between psychological and social conditions. This more nuanced approach is understandable in light of the fact that it can be difficult, in some instances, to separate a condition from its context, as reflected in a recent tendency in the psychiatric literature demonstrating the ethnocentric nature of diagnostic manuals such as the DSM-5, and underscoring the need for such classificatory tools to pay greater heed to the context and culture inherent in mental illness.Footnote 103 For example, post-traumatic stress disorder, by its nature, takes into account a previous event or circumstance in diagnostic terms. As Slovenko asserts, ‘PTSD is one of the few psychiatric disorders listed in the DSM-III that are defined in part by the environment.’Footnote 104 Other conditions that are difficult to disentangle from a defendant’s wider circumstances include addiction, trauma, and developmental immaturity. A brief account follows of how the law presently deals with each.
Addiction is increasingly recognised as a social problem,Footnote 105 and so stands at the fringes of the diminished responsibility defence because it invites information beyond a purely capacity-based framework in evaluating blameworthiness. The law deals with this complex issue by distinguishing voluntary from involuntary intoxication and focusing on the effect on the individual defendant. The position in England and Wales, Northern Ireland, and now Scotland is that a defendant cannot rely on voluntary acute intoxication to form the basis of a diminished responsibility defence.Footnote 106 However, the House of Lords in Dietschmann held that intoxication does not preclude the defence where the accused had an unrelated mental abnormality.Footnote 107 In the subsequent case of R. v. Wood,Footnote 108 the court held that the jury, in addressing a plea of diminished responsibility in the context of alcohol dependency syndrome, must consider whether it had been established that the accused’s disorder was of such a degree that it constituted an ‘abnormality of mind’ from a disease or illness, and, if so, whether his mental responsibility for his actions at the time of the killing was substantially impaired as a result.Footnote 109 The case of R. v. StewartFootnote 110 reaffirms the rationale behind Wood as fairly reflecting developments in contemporary understanding of alcohol dependency syndrome in the context of diminished responsibility, which could, even in the absence of visible brain damage, constitute an abnormality of mind from a disease or illness. On that basis, the approach taken in R. v. TandyFootnote 111 was deemed too rigid.Footnote 112 Though the more recent case of R. v. FoyFootnote 113 does not change this position, it is worth pointing out here that, notwithstanding a psychotic episode, the circumstances were deemed not to meet the requirements of recognised medical condition owing to the fact that the defendant was also voluntarily intoxicated at the time.Footnote 114 In Ireland, intoxication is specifically excluded from the definition of ‘mental disorder’ under the 2006 Act, however, it is unclear whether this includes both voluntary and involuntary intoxication as is the case with addiction.Footnote 115
In addition, the notion of reduced culpability on the basis of past trauma or abuse is largely unpopular, particularly since Dershowitz coined the term ‘abuse excuse’,Footnote 116 the catchy phrase imbuing the concept with suspicion and a sense that the defendant is ‘playing the victim card’ in order to ‘get off lightly’. However, recent studies have shown how trauma can impair to a significant degree the capacity of the accused to control their actions in certain circumstances, and criminal justice agencies are beginning to take note.Footnote 117 Though experiencing a traumatic event may seem ‘off the books’ for the purposes of a diminished responsibility defence, it has formed the basis of a defence in Scotland, where courts have supported defences based on past/childhood abuse or trauma, battered person’s syndrome,Footnote 118 and sexual abuse. Childhood trauma has also been used to support a diminished capacity defence in the United States,Footnote 119 and there are scholars that argue in its favour as a factor that ought to reduce culpability.Footnote 120
Developmental immaturity has also caused controversy in terms of whether it should amount to a defence in the criminal law.Footnote 121 Though it was recommended by the Law Commission of England and Wales in 2005 that it ought to be capable of forming the basis of a diminished responsibility defence,Footnote 122 and received some support from academia and core stakeholders,Footnote 123 the proposal was ultimately sidelined in the context of considering reform of the partial defence.Footnote 124 Elsewhere the Commission recommended instead a wider examination of the law of murder as it relates to children and young people.Footnote 125 Reluctance to engage with the condition in the context of diminished responsibility fails to take seriously a large body of neuroscientific evidence, which shows that adolescent neurobiological immaturity is an uncontroversial fact.Footnote 126 There is strong support for the contention that the brain continues to mature until the early twenties particularly in relation to the following factors: ‘impulsivity, judgment, planning for the future, foresight of consequences’ – characteristics that are integral to the assessment of an individual’s moral culpability.Footnote 127 In practice, immaturity alone is unlikely to be deemed sufficient to amount to the basis of a diminished responsibility defence without a specific diagnosed mental disorder.Footnote 128 However, it is noteworthy that the English Sentencing Council has inserted developmental immaturity as a mitigating factor for diminished responsibility at the post-verdict stage.Footnote 129
The UPD Approach
Overall, the courts have demonstrated some flexibility in their interpretation of what is deemed appropriate to form the basis of a diminished responsibility defence. This attitude hints at an appetite for a more humane, and nuanced, approach to blame evaluation than was perhaps intended by lawmakers. As discussed in Chapter 5, the universality of the UPD is reflected in its inclusion of a wider range of conditions and circumstances within the defence. Notwithstanding the stigmatising terminology used in the Scottish definition, it best captures the spirit of the RPA because it represents the least medicalised version as the basis of an excusing condition . This approach is also reflected in Morse’s motivation for his general partial excuse which seeks to provide a solution to the issue of ‘new syndrome’ excuses.Footnote 130 Instead of creating new excuse definitions for each syndrome that might present as a potential basis for an excusing condition, Morse’s proposal would accommodate such excuses within the remit of an adjusted framework that still relies on rational capacity. The UPD does similar, but with a broader scope in relation to mental functioning as outlined earlier, and with the inclusion of a wider situational context (reflected in the term ‘circumstance’ in the proposed blueprint outlined in Chapter 8). Moving away from readily accepted mental disorders – this approach ensures that those conditions that might be described as straddling the condition/circumstance divide, like addiction, trauma, and developmental immaturity – are clearly accommodated within the UPD, which accords with the flexible approach afforded to these categories in practice. Moreover, in terms of wider circumstance, it is envisaged that the UPD could apply to an immediate context, but also to more enduring prior factors such as particular life experience, familial circumstances, and cultural contexts, in order to reflect the dynamic nature of agency as mandated by the RPA.Footnote 131 The more challenging of these, like cultural defences and provocation in the context of domestic abuse, are considered further in Chapter 8.
Of course, it is not the basis of the defence alone that decides the fate of the accused; the nature and impact of a condition on the defendant plays a significant role in assessments of culpability for the purposes of diminished responsibility.
Substantial Impairment
In making their assessment, the jury/judge is required to pay heed to the way in which the condition impacted the defendant’s rational and/or volitional capacity. This step is significant in terms of demonstrating that the definition of ‘substantial impairment’ is given a common usage meaning by the courts, and also that the question of the defendant’s impairment is ultimately for the jury to decide upon, and not the expert, though this assertion has been challenged more recently in England and Wales. Because this step is not restricted by scientific evidence, however, it supports the view that the core component of partial excuse is normative in nature, and so has the potential to be more responsive to cultural shifts and wider scientific developments than the law is currently.
England and Wales, Northern Ireland and Scotland all make reference in one form or another to ‘substantial impairment’ of the defendant’s capacities.Footnote 132 Over the years, ‘substantial’ has been interpreted to mean more than ‘trivial or minimal’ impairment,Footnote 133 or moderate impairment,Footnote 134 but does not have to amount to borderline insanity.Footnote 135 Post the 2009 Act, the case of R. v. BrownFootnote 136 confirmed that the phrase is not intended to be any different from its meaning under the old law,Footnote 137 though it makes reference to the defendant’s capacities rather than their moral responsibility. The threshold of substantial impairment was reviewed thoroughly by the Supreme Court in the case of R. v. Golds, where Lord Hughes confirmed that the term is to be conferred with its ordinary meaning and not to be defined by the trial judge.Footnote 138 The only exception to this direction is where, in the view of the judge, there is a likelihood that the jury might misunderstand what is meant by the term. If that is the case, then the judge should instruct the jury that ‘whilst the impairment must indeed pass the merely trivial before it need be considered, it is not the law that any impairment beyond the trivial will suffice’.Footnote 139 The Court found that the trial judge in Golds had correctly left the issue with the jury and they found the defendant guilty of murder, notwithstanding uncontested evidence from the psychiatric experts as to the defendant’s psychotic episode at the time of the offence. Though the judgment in Golds appears to clarify the question of interpretation regarding ‘substantial impairment’ in terms of leaving it to the jury, there is some concern that it resulted in a narrowing of the defence owing to Lord Hughes’ understanding of substantial as ‘significant and appreciable’ or ‘considerable’.Footnote 140 That said, Lord Hughes also endorsed the Scots law approach in Galbraith, where the Appeal Court employs a common-sense psychology approach to language, saying that there must have been something ‘far wrong’ with the accused, which affected the way he acted.Footnote 141 Whether Golds has altered the threshold of substantial impairment in a meaningful way remains to be seen; nevertheless, its interpretation rests as a question for the jury in the first instance.
Perhaps the more confusing element of Golds, however, stems from Lord Hughes’ interpretation of the role of the psychiatrist in interpreting the ‘substantial impairment’ component. The Supreme Court held that the question for the jury in this case was not about the meaning of the word substantial as discussed previously, but rather whether the accused had been in the grip of a psychotic episode at all at the time of the act, notwithstanding the fact that the experts agreed that the defendant had a medical condition that substantially impaired his abilities. This latter point appears to endorse expert opinion on the question of ‘substantial impairment’ despite the fact that the question has been recognised by the Law Commission as a question for the jury.Footnote 142 Indeed, Lord Hughes goes on to say that the offering of an opinion on the issue is ‘a matter for individual judgment’ on the part of the expert themselves.Footnote 143 This view appears to reinforce an assumption apparently held by the psychiatric profession that they are required to express an opinion on this issue, even though it is traditionally a matter for the jury.Footnote 144 And, indeed, perhaps it is inevitable that an expert would provide evidence on the impact and degree of the impairment, and perhaps the addition of this information is useful to the jury in making a decision. What is important to emphasise, however, is that the ultimate question is for the jury alone to address and, as such, they are entitled to override psychiatric evidence (even where uncontested) if they are of the view that the defendant is sufficiently morally blameworthy to be convicted of murder, and not manslaughter.
The UPD Approach
Overall, the UPD recognises the value of assessing the level of impairment experienced by the defendant given that the UPD does not result in a full acquittal. The term is sufficiently flexible to delegate to the jury the normative task of assessing the impairment as a matter of degree in a given case. That said, it may be appropriate for the jury’s decision to be informed by expert evidence in some cases, as explored in a later section and in Chapter 8.
The Causal Link
Though remaining ambiguous in the new defences in Scotland and Ireland, the law in England and Wales and Northern Ireland endorses the Law Commission’s recommendation that the mental condition element must be shown to be ‘an explanation’ for the defendant’s conduct, thus ensuring that there is an appropriate connection between the abnormality of mental functioning and the killing.Footnote 145 This particular amendment seeks to tackle the criticism that it has never been entirely clear whether, under the existing law, the abnormality of mind/mental functioning must, in some sense, ‘cause’ the defendant to kill.Footnote 146 While certainly resolving the question as to whether causation is a requirement of a successful diminished responsibility defence, the definition fails to shed any light on the difficulties inherent in proving the link between the defendant’s conduct and the ‘abnormality of mental functioning’. Furthermore, from Mackay and Mitchell’s study, it appears that consideration of this aspect is relatively hit and miss,Footnote 147 prompting the authors to tentatively conclude that ‘report-writers are frequently not addressing the “explanation” requirement under the new law’.Footnote 148 Underpinning this reluctance is a reality that few wish to voice regarding the burden of untangling the ‘abnormal’ behaviour from the normal. As Hallett puts it, ‘Although psychiatric evidence may play an important role, demonstrating that a mental disorder had a causative role in the killing will often be an impossible task for anyone.’Footnote 149 In other words, just as it is impossible for the jury to get inside the mind of the individual at the time of the offence, so too is it impossible for the expert psychiatrist.
The UPD Approach
The blueprint in Chapter 8 proposes two points of connection on the basis that linking certain features of the defence is more likely to assuage fears of determinism, as discussed in more detail in developing the bounded causal theory in Chapter 7. The first connection is between the condition/circumstance and the impaired mental functioning, and the second is between the impaired mental functioning and the defendant’s conduct. It is recommended that the first requires greater specificity in approach than the second; though, again, given the normative nature of the evaluation, a more flexible approach is recommended, as supported by Robinson’s proposal for a general mitigation at the pre-verdict stage.Footnote 150 Robinson argues that given the individual is still deemed criminally responsible, it is less important to establish the causal link and so the question rather ought to be ‘whether the disturbance at the time of the offense makes the offender noticeably less blameworthy than an offender committing the same offense without the disturbance’.Footnote 151
Similarly, Lambert provides a useful example in this regard in promulgating her poverty/scarcity defence. Her argument asserts that ‘one cannot raise a claim of GPR solely on grounds that one is poor; there must be some further link to an excusing condition.’Footnote 152 As such, she outlines the requirement to show a ‘direct situational link’ between poverty and cognition in order for a partial defence to ‘break the stalemate’ between deprivation-based defences and questions of criminal responsibility.Footnote 153 For Lambert’s proposal, this would come in the form of evidencing how ‘scarcity’ can leave a largely consistent mark on those subject to it in that, notwithstanding the cause, a scarcity mindset results in a form of mental ‘tunnelling’ or ‘hyper-focused attention’ directed towards the source of the scarcity,Footnote 154 resulting in the person experiencing a psychological burden or ‘bandwidth tax’ such that they have a reduced cognitive and volitional capacity.Footnote 155 It is envisaged that this overall approach can work with other scenarios beyond poverty too, provided a connection is made. Finally, in terms of feasibility, it is noteworthy that the Irish defence (discussed further below) does not draw out a specific requirement for a causal link between the mental disorder and an impairment, rather only requiring that the impairment did not reach the level required of the insanity defence.Footnote 156 How this might be evidenced in the UPD is discussed further in Chapter 8.
The Persistence of Normativity and the Limitations of Psychiatric Evidence
An analysis of the law relating to diminished responsibility reveals a trend towards pathologising the defence through the use of medicalised wording, particularly in England and Wales and in Ireland. The advancement of a medical model may well be informed by valid fears regarding the extent to which the defence is used to partially excuse those who do not have a clear psychiatric diagnosis, for example, the mercy killer;Footnote 157 however, these fears do not appear to be mirrored to the same extent in the operation of the defence. Indeed, the preceding analysis reveals a broader and more pragmatic approach taken to the interpretation of diminished responsibility than one might surmise from the legislative definitions of the defence. Though experts may overstep the mark, and courts may even encourage them to do so on occasion, it remains the case that the normative nature of the defence persists, as demonstrated by the strong legal underpinning of abnormality of mind/mental functioning; the range of conditions that are considered to come within a defence; the ordinary usage recommendation in respect of substantial impairment; and the lack of enthusiasm in practice about the causal link requirement.
The prominence of normativity in the defence is innately connected to the standing of the jury, whose role is not merely fact-finding, but also to resolve multifarious moral questions in accordance with the law.Footnote 158 This task is particularly significant in the context of criminal excuses where, according to Raphael, ‘juries are the best-suited institutional actors for capturing societal norms and shared moral values regarding criminal wrongdoing’.Footnote 159 In coming to their decision, the jury hears testimony from expert psychiatrists on the components of diminished responsibility to varying degrees, as outlined previously. Psychiatry’s contribution in this manner is a boon to the law because it has, for one thing, resulted in a move away from arbitrary intuition-based evaluations by the jury towards empirically informed assessments of a defendant’s mental state, and beyond.Footnote 160 In this way, psychiatry has assisted decision-makers with the interpretation of legislation, and has informed the development of criminal excuses to a significant extent.Footnote 161 Notwithstanding the more positive aspects of the union between law and psychiatry,Footnote 162 however, the increasing reliance on a medical model of diminished responsibility risks undermining the normative nature of the defence. This move is problematic because it is pushing scientific testimony beyond its competency: for, while an expert’s opinion might bring clarity to a defendant’s mental condition and how it might manifest in their behaviour, they are not in the business of making a moral judgement on the defendant’s blameworthiness. Accordingly, and without detracting from the influence of empirical science to questions of substantive law and evidence, it is necessary to acknowledge the limitations of such contributions in the context of determining criminal culpability, in particular, under two themes. The first theme relates to the nature of psychiatric testimony itself, and the second considers what is lost by the law by way of its moral development in relying exclusively on psychiatric diagnoses to inform the basis of the defence.
The first theme reflects on the nature of psychiatric testimony which appears, at times, shrouded in a seemingly irreproachable aura, in part stemming from a wider phenomenon of ‘system arrogance’ evident in writings on medical culture in recent years.Footnote 163 In addition, the impression of authority arguably derives from the high expectation placed on experts by the court to deliver certainty with authoritative force. For example, Walker contends that most judges, counsel, and even juries tend to consider a psychiatric diagnosis as the ‘exact equivalent’ of a physician.Footnote 164 Such an approach, he surmises, is bolstered by the way the expert is required to express themselves in court: ‘[h]e must achieve an objective which does not appeal to him by gymnastics for which he is not trained’.Footnote 165 What is required of them is a clear, professional, and confident statement regarding the elements of the defence, up to and occasionally including the ultimate question. For Walker, then, the psychiatrist is therefore ‘tempted – one might also say invited – to slap an impressive label on the accused in order to ensure that he arrives at what seems to [him] to be the right destination’.Footnote 166 This quiet interchange between the law and the expert is perhaps reflective of the fact that there exists a level of mistrust by lawmakers and practitioners regarding the average juror’s ability to discern what is required of them. As McEwan notes: ‘[T]he law of evidence represents an uneasy compromise between the insistence that fact-finders apply their own common sense to questions of fact and the nagging doubt harboured by lawyers that many questions of fact are beyond them.’Footnote 167 Psychiatry, though a branch of medical science, is not equivalent to physical medicine, however, and there is a sense that this is not adequately recognised by the law. For instance, Fulford points to the fact that psychiatrists diagnose and characterise mental disorders on the basis of experiences and behaviours, as opposed to underlying causes, in contrast to physical medicine.Footnote 168 Further, psychiatrists themselves have expressed unease about testifying in respect of some of the components of the defence. Notwithstanding recent developments in the law, psychiatrists argue that ‘there is no sound psychiatric methodology’ to address some of the questions they face; for example, in relation to the connection between a defendant’s behaviour at the time of the killing and their disorder.Footnote 169 As such, there is evidence of a gap between what is expected of the psychiatric expert in court and what they are capable of delivering.
The division between expectation and reality is borne out in terms of diagnostic classification, clinical process, and interpretation of legal criteria by practitioners. There is a lingering sense of unease in parts of the scientific world that, notwithstanding a major upheaval to practice approach under the DSM-III towards more objective categorisation, the diagnostic modelling upon which psychiatric evidence relies is inherently problematic, with one author recently describing it as a ‘disingenuous categorical system’.Footnote 170 For example, one line of study argues that the current model fails to adequately recognise the role of trauma in mental health issues.Footnote 171 Another criticises attempts by the DSM-5 to address accusations of ethnocentricity, arguing that the manual continues to favour biological psychiatry to the detriment of cross-cultural perspectives.Footnote 172 Additionally, the process which clinicians undertake to arrive at a diagnosis has raised questions in terms of its validity and consistency, with one commentator noting that ‘the unreliability of psychiatric diagnosis remains a serious problem’.Footnote 173 Finally, diagnostic problems are also evident in the courtroom on occasion,Footnote 174 where experts can clash over the primacy of a particular diagnostic manual, or engage in ‘unseemly battles’ where professional views diverge.Footnote 175
The second theme considers the reliance of the law on psychiatric testimony from a negative perspective – in other words, what factors are overlooked when attention is given only to psychiatry as the means of informing the basis of a diminished responsibility defence, and how is moral progress in the law thus impeded? Part II outlined and explored the impact of the narrow view of personhood inherent in the dominant rational agency paradigm underpinning the criminal law. This restrictive view is reinforced by the contribution of psychiatric testimony, which can also be accused of ‘covering up’ the link between social context and criminogenic behaviour,Footnote 176 thus placing criminality solely in the psyche of the defendant rather than recognising it as a societal problem. Given its contribution to pathogenic vulnerability, the RPA recommends that the criminal law itself ought to pay heed to crime as a social problem, as explained in Chapter 4, in particular. Suffice it to say here, then, that individualisation serves to isolate the defendant and consequently their mental condition, resulting in an incomplete account of their moral story for the purposes of evaluating blameworthiness,Footnote 177 for example, by excluding evidence relating to the impact of prior factors that derive from broader aetiologies, such as social and economic deprivation and adverse childhood experiences.Footnote 178 As a result, the criminal law sabotages the advancement of social justice in the realm of culpability evaluation by failing to recognise agency as vulnerable.
Furthermore, using expert psychiatric testimony to bolster an individualistic account leads to a problem of legitimacy, by occasionally revealing a fissure between the law ‘on the books’ and the law in practice. This issue is highlighted by the way in which the law uses psychiatric evidence to support its conclusions, as is demonstrated by the fact that psychiatric testimony occasionally overreaches not just the legal criteria of mental condition defences but its own criteria of what constitutes mental disorder or abnormality of mind/mental functioning where a compassionate or merciful response to crime is required.Footnote 179 For example, in the case of mercy killing, the Criminal Law Revision Committee commented that ‘legal and medical consciences are stretched to bring about a verdict of manslaughter by diminished responsibility’.Footnote 180 Even under the 2009 legislation, it would appear to be the case that the new law in England and Wales is ‘sufficiently malleable so as to meet, where necessary, the needs of those mercy killers who do not satisfy the defence on their own merits’.Footnote 181 So, in attempting to meet the justice requirements of a case, the law essentially undermines its own legitimacy, by creating, as Gibson notes, ‘a new disconnect between what the law says and what it does’.Footnote 182 This threat can be overcome by either realigning practice with principle, or vice versa. To marry practice to principle, the law would need to take a more stringent approach to how it assesses the basis of a diminished responsibility defence, for example, legislation could specifically define the diagnoses that can form the basis of a defence. Alternatively, to marry principle to practice, the law would need to reflect the need for flexibility informed by a broader evidence base in legislation, for example, by allowing consideration of the wider (and relevant) circumstances of the defendant at the point of exculpation. Needless to say, the latter approach is recommended in terms of moving towards a criminal law informed by the RPA, in light of its more contextual underpinning.
But the question remains, is the jury up to the normative task of evaluating blameworthiness? A fear underpinning jury decision-making is framed in terms of the notion of the ‘sympathetic jury’. For example, Williams has said that ‘on the flimsiest of evidence juries will avoid murder convictions in sympathetic cases’.Footnote 183 However, this assumption does not chime with evidence that suggests that juries are more likely to convict of murder in the context of diminished responsibility than if the defence is pleaded and dealt with by a judge.Footnote 184 This point is made more pertinent by the fact that murder convictions in this context appear to be increasing following the introduction of the 2009 Act.Footnote 185 Further, juries have been known, albeit infrequently, to go against the opinion of experts and endorse a murder conviction, even where consensus exists between the experts as to the defendant’s diagnoses and its impact.Footnote 186 The low success rate of the insanity defence is also evidence of jury reluctance to exculpate.Footnote 187 This evidence suggests that juries are no pushover.
In the face of advancing scientific discoveries relating to impulse control, emotion, behaviour, and cognition,Footnote 188 in addition to evidential ambiguity pertaining to psychiatric testimony, it becomes more important to underscore the conceptual hinge on which the defence of diminished responsibility rests. For, it is the central focus on the capacity of the accused that acts as a filter in respect of the potential aetiology of the defence, and any evidence that pertains to it. With others,Footnote 189 I argue that the defence is ultimately a moral evaluation of the defendant’s blameworthiness by the jury,Footnote 190 and not just a ‘psychiatric matter’, as per the judgment in Brennan.Footnote 191
Fore-fronting the moral question does not necessarily involve displacing the role of the expert, however. Rather, taking the role of the jury more seriously should involve an increase in the relevant information available to them through access to a broader field of expert testimony in order to give credence to their power to decide on the ultimate issue. This shift may go some way towards realigning the power as between jury and expert, which has historically leant towards the latter. For example, Ward distinguishes diminished responsibility for its elevation of the expert from the role of ‘adviser’ to one of ‘authority’ since its introduction in England and Wales:Footnote 192
The courtroom … is a far from ideal forum in which to conduct a subtle moral evaluation of a defendant’s character. But so long as such an evaluation has to be made, the expert can best assist the jury to make it by acting as an adviser rather than an authority.Footnote 193
From a more recent perspective, let us not permit intentions around the medicalisation of the defence to detract from the proper role of the jury as fact-finder, influenced, though not displaced, by the role of the expert. Both sides are agreed on this, by and large. As Nathan opines: ‘In framing their opinion, the psychiatrist needs to remember that the questions posed by this partial defence are matters of fact that are entirely within the jury’s province. Psychiatric evidence may be influential, but it is not determinative.’Footnote 194 Similarly, from a legal perspective, Ormerod and Laird emphasise that the significance of expert evidence does not remove the ultimate issue from the jury; instead, it facilitates more evidence-informed decision-making.Footnote 195
To this end, the UPD explicitly highlights the normative function of the jury through requiring them to reflect on the moral appropriateness of their decision. The practical challenges that such an approach may face are discussed in greater detail in Chapter 8.
Conclusion
This chapter has provided an account of diminished responsibility as a template for the UPD proposal. It has unpacked key components of the defence and shown how its operation reveals a penumbral approach to its interpretation, both in a legal and occasionally medical context, through the inclusion of conditions that sit at the edge of the intended meaning of ‘recognised medical condition’ and ‘abnormality of mind/mental functioning’. Further, the chapter has raised concerns about attaching too formally to psychiatric expert testimony as a means of shaping evaluations about moral culpability in the context of partial excuse. Indeed, the flexible approach of the courts in interpreting the defence suggests a stomach for moral complexity, enough, perhaps, to say that a broader causal basis for a defence is not as antagonistic to the present doctrine as one might assume. As such, the UPD builds upon the more generous instincts of practice by recognising a broader basis to the defence that adheres to the reality of complex causality in the lives of defendants, but in a way that aligns with the existing capacity-based account. Moreover, this chapter has argued for the reclamation of the normative nature of the test as a means of providing the necessary constraints on the decision-maker in order to avoid the pitfalls of an ‘evaluative free for all’. Finally, the analysis serves as a springboard for the development in Chapter 7 of a bounded causal theory as a rationale for partial excuse, and the proposed UPD – one that provides a more nuanced explanation of the doctrine given that some of the conditions accepted in practice are not adequately represented by a capacity-based account alone.
