The crime was the disease

A diagnosis​ of mental illness has many meanings, not all of them clearly stated. It confines itself to the language of the clinic but its reach extends far beyond it. It confers many, often hard-won, legal rights to employment, treatment, educational support and state benefits; equally it can remove your children from you, oblige you to undergo treatment against your will or take away your liberty. Whether psychiatrists acknowledge or even want these powers, they come with the territory. It’s ironic, to say the least, that conditions whose biomedical basis is so uncertain should generate diagnoses that are so consequential.

These statutory powers aren’t a recent addition. Mental diagnosis began not in the hospital or the laboratory but in medieval courts of law. Under the Saxon legal code, justice had been conceived primarily as the restitution of wrongs. Everybody was straightforwardly liable for their actions, and if the crime was committed by someone of unsound mind, their family owed the forfeit on their behalf. The canon law of the Normans introduced the idea of moral guilt, which involved judging the intentions and mental state of the perpetrator. The first recorded acquittal on grounds of unsound mind dates from 1505, though the principle was by then long established. The 13th-century jurist Henri de Bracton, who formalised the growing body of case law under Henry III, had stressed that ‘in misdeeds we look to the will and not the outcome,’ and consequently ‘a madman is not liable.’

From this point on, madness was defined by legal concepts such as mens rea (guilty intention) and non compos mentis (unsound mind). ‘Madness’ itself came to specify a temporary condition, in contrast to ‘idiocy’, which was congenital and incurable; the property of the mad was held in trust pending their possible recovery whereas that of ‘idiots’ or ‘fools’ reverted to the crown. Non compos mentis was rendered in English as ‘insanity’, a word first recorded in a court case of 1590. It was only at this point that ‘sanity’ took on its modern meaning: previously it had referred, like the French santé, to general health. In this limited sense it was the insane who defined the sane, not vice versa.

During the 18th century mad-doctoring emerged as a medical specialism; by the late 19th, its practitioners were referring to themselves as ‘alienists’ and eventually ‘psychiatrists’. Over this period Joel Eigen’s contention is that ‘by far, the most powerful structural element in the evolution of medical psychology, and particularly diagnosis’, was the courtroom. Mad-Doctors in the Dock is the concluding volume in a trilogy spanning twenty years based on Eigen’s now exhaustive study of the Old Bailey Session Papers, the transcripts of every criminal case in London’s central court from the 17th century until 1913. Nearly a thousand of these cases involved questions of insanity (between four and eight per thousand, by Eigen’s estimate) and they track the evolution of mental diagnoses into ever more precise and legally inflected forms.

Until 1800, Eigen has established, ‘English legal opinion had mandated that only a total madness – a complete want of understanding and memory’ – could compel a not guilty verdict. After that date the category of ‘unsound mind’ began to be qualified and refined by such concepts as delusion, delirium, monomania, moral insanity, masked epilepsy and melancholia before reaching this final volume’s emblematic diagnosis, homicidal mania. Eigen’s first volume, Witnessing Insanity (1995), surveyed the evidence presented in insanity pleas and its reception in the courts; the second, Unconscious Crime (2003), focused on pleas involving somnambulism, epilepsy, hypnosis and other twilight states of consciousness in which the accused was said to be legally ‘absent’. Mad-Doctors in the Dock recapitulates elements of both, and of the work that undergirds the whole project, Nigel Walker’s Crime and Insanity in England, Vol. I (1968). Although it breaks less fresh ground than its predecessors, its focus on diagnosis propels it to the heart of the matter. As he puts it in his preface, after thirty years scrutinising the Session Papers for answers, ‘now I know the question.’

The rise of the insanity defence was one consequence among many of the growth in legal representation that culminated in the right to a full defence in criminal trials enshrined in the Prisoner’s Counsel Act of 1836. Over the same period other forms of expert medical evidence – toxicology reports, surgeons’ assessments of the cause of injuries – had a transformative effect on jury trials. Expert witnesses were called by prosecution and defence alike and it became common for them to buttress the arguments of opposing sides, blurring the line between science and advocacy. This was a period during which the fledgling profession of mad-doctoring was struggling to establish itself in the asylums, where its role in treating madness was challenged by advocates of ‘moral treatment’, the non-medical approach developed and spread by Quaker societies. Mad-doctors were being elbowed off the statutory bodies that allowed lay preachers and social reformers to licence and inspect the asylums, yet at the same time were in ever greater demand for their opinions on legal conundrums such as mens rea, lucid intervals, nervous pathologies or irresistible impulses.

Despite the doubts about its efficacy in mental treatment, after the introduction of the 1774 Vagrancy Act, medicine established itself securely in prisons and asylums, where resident doctors were eventually mandated by the 1845 Lunacy Act. Those who took on this role witnessed insanity with a regularity rarely granted to previous generations. Before the 19th century most medical witnesses in the courtroom had known the accused and were able to testify to their normal character. By mid-century most who took the stand at the Old Bailey had met them for the first time in Newgate, Holloway or Bethlem. Their testimony stressed the weight of their experience – ‘among my 850 patients at Hanwell Asylum’ – and deployed technical language to stress its scientific basis. In the process the voices of the accused were muted. Where the prisoner’s statement had once been the centrepiece of the defence, it was now no more than grist for the learned disputations of the experts.

Eigen’s starting date of 1760 marks the first time that specialist medical evidence was summoned to adjudicate insanity in an English courtroom, but the case that really launches his narrative is that of James Hadfield, who on 15 May 1800 was arrested in the Drury Lane Theatre after firing a pistol at George III as he was blowing a kiss to his subjects from the royal box. There was no question that Hadfield had acted with deadly intent. He had loaded his pistols carefully and aimed like the ex-soldier he was; his first words to the policeman who wrestled him to the ground were: ‘Did I get him, did I get the king?’ His defence counsel Thomas Erskine, the Whig MP who had faced down Pitt’s government in the treason trials of 1794, disputed none of the facts but argued for dismissal even so. Hadfield had been under the illusion that he was God’s instrument, and that by killing the king (and thereby martyring himself) he would trigger the second coming of the messiah. Given this delusion the act was not regicide but a moral and religious duty.

Erskine called a physician to testify that Hadfield was non compos mentis owing to terrible head injuries received while fighting in the Napoleonic Wars in the service of king and country; it would be barbaric to convict him of high treason, for which he might be hanged, drawn and quartered. The lord chief justice was persuaded to halt the trial and set Hadfield free. His release led to a public outcry and the swift passage of the Criminal Lunatics Act, under which those acquitted on grounds of insanity but too dangerous to be released could be detained indefinitely. It was a sensational outcome, though precedent for Erskine’s case stretched back to Henri de Bracton’s medieval opinion that ‘a crime is not committed unless the will to harm is present.’ Hadfield’s act was meticulously premeditated, but his intention was not criminal.

The verdict had far-reaching effects on the insanity defence. The simple criterion of ‘unsound mind’ or ‘total madness’ was complicated by the possibility of a ‘partial insanity’ – limited to particular subjects, or moments, or contexts – in which a delusion bore specifically on the criminal act. The new diagnosis, Eigen argues, ‘underscored a growing separation of legal from moral wrong’, and of expert medical judgment from popular opinion. Insanity moved inwards, no longer identified by overt behaviours but by inscrutable mental states visible only to experts. ‘A speciality, perhaps the first of the English medical specialities, was emerging with the active participation of the state.’

But the complexities of partial insanity were hard to square with the court’s demand for a clear-cut binary verdict. Medicine presented differences in degree between sanity and insanity, where the law sought differences in kind. Expert witnesses on opposing sides offered competing definitions of delusion. The prevailing view before 1800 had typically drawn on Locke’s cognitive theories in which madness was a disorder of the intellect, ‘an incorrect association of familiar ideas’. This was now challenged by biological models in which delirium and delusion were conceived as pathologies of the brain or nervous system, phrenological imbalances or hereditary weaknesses. Still other experts argued that the issue, far from being lack of reason, was a derangement of the passions or the will. This was the basis of the ‘moral insanity’ diagnosis formulated in 1835 by James Cowles Prichard: a ‘madness consisting in a morbid perversion of the natural feelings’ by which the cognitive faculties were ‘suspended’ or shut down. When Prichard’s follower John Conolly, the celebrated superintendent of Hanwell Asylum, was asked by a judge in 1850 whether the accused was able to tell right from wrong, he replied coolly: ‘We medical men do not consider that a question of distinction at all.’

It was against​ this background that judges adopted the McNaughton Rules of 1843, which instructed juries to confine themselves to the question of whether the accused knew at the time that he or she was acting contrary to law. ‘It is tempting,’ Eigen suggests, to see the rules as ‘the judiciary’s attempt to enshrine delusion as the sole medico-legal concept of significance’. In many respects the rules were a reversion to the norm that had prevailed before 1800, but they often proved inadequate, not least in the case from which they derived. Daniel McNaughton was a successful Glasgow businessman and a political radical who in 1841 became convinced that he was being persecuted by Tory spies. Suffering from crippling pains in the head and advancing paranoia, he conceived a vendetta against Robert Peel, then prime minister, bought pistols, travelled to London and, though apparently intending to assassinate Peel, fatally shot his private secretary Edward Drummond. ‘The Tories in my native city have compelled me to do this,’ he claimed in court. ‘They follow and persecute me wherever I go.’ McNaughton’s partial insanity, the prosecution claimed, was not so severe as to preclude his knowing right from wrong. The defence countered that, like Hadfield’s, it was a delusion that if true would have justified the act; but they also called distinguished medical witnesses who testified that his condition had robbed him of all self-control, amounting to an impulse ‘so strong that nothing short of a physical impossibility would prevent him from performing an act which his delusion might compel him to do’. The jury found McNaughton not guilty on grounds of insanity, and he was confined for life in Bethlem and Broadmoor. But if it was true that he had been subject to an irresistible impulse, his ability to tell right from wrong was surely irrelevant.

‘Irresistible impulse’, at this point, was a symptom in search of a convincing diagnosis. Prichard’s moral insanity proposed a ‘lesion of the will’ as the underlying pathology, an uneasy phrase that combined a notional brain defect with an immaterial quality of mind. As such it was unsatisfactory to many judges, who after 1843 saw it as an attempt to muddy the clarity stipulated by the rules. Eigen holds it up as an example of the role the courts played in sifting the experts’ theories and shaping diagnosis. Confronted with John Conolly’s high-handed testimony about the irrelevance of the standard right-wrong question, the judge turned to the jury in exasperation: ‘Experts in madness! Mad-doctors! … If you can make sane evidence out of what they say, do so; but I confess it’s more than I can do.’ Judges regularly used their prerogative to admit or dismiss evidence, to advise the jury how to weigh it, or to decline the verdict if they felt insanity had not been sufficiently demonstrated. Jurors, for their part, could and did ignore expert testimony if the diagnosis seemed contrived or a poor fit with their impression of the figure in the dock. They were known to acquit on grounds of insanity even after defence and prosecution experts had both deemed the offender sane. And they weren’t impressed by the notion of moral insanity: to them it seemed insufficiently distinct from simple fecklessness or loss of control.

A generation later, however, the irresistible impulse was supported by a more confident biological model and a social context in which it had become more persuasive to juries. These are the forces, Eigen argues, that led to the emergence of homicidal mania as a signature diagnosis of the late 19th century. In the years following the McNaughton case Britain entered ‘an age when music-hall hypnotists and salon mesmerists brought before the public a frightening display of individuals pursuing physical ends not of their own choosing. In the courtroom these cultural anomalies were supplied by sleepwalkers, automatons and a new variation on an old disease: epilepsy.’ This is the territory he explored in his previous volume, Unconscious Crimes, which considered a series of sensational cases in which the defence argued successfully that the accused had been mentally ‘absent’ during the act. The diagnosis of ‘suspended consciousness’ or vertige épileptique (the term used in French medicine for the mental state induced by a non-convulsive seizure) offered a physiological basis for states of automatism and amnesia in which violent criminal acts might be committed but the sine qua non demanded by the McNaughton Rules, a delusion connected specifically to the crime, didn’t apply.

Homicidal mania​ emerged ‘at a critical moment in the histories of madness, forensic psychiatry and the (then-emerging) advocacy bar’. It was frequently proposed in cases where the usual motives of profit or revenge were lacking, and particularly where the victims were the nearest and dearest of the accused. If a mother testified that she was ‘taking the child to heaven to see its father’, the right-wrong question seemed beside the point: the act was a consequence not of her incorrect reasoning but her morbid emotional state. When in 1895 a judge asked the physician Henry Charlton Bastion what homicidal mania was, he replied that ‘a man having certain tendencies will occasionally, without warning or provocation, commit a certain act of violence … a gust of impulse comes over him so suddenly that he is not in a position to weigh or balance whether such a thing is right or wrong.’ In some cases medical witnesses argued that a lapse in consciousness had occurred, but in others the accused recalled the act with dreadful clarity. In these the phenomenon of ‘double consciousness’ was invoked: two personalities each unaware of the other, one that tenderly suckled the child as the other strangled it. Homicidal mania – like other criminally defined diagnoses such as pyromania or kleptomania – was plausible in inverse proportion to a sane or discernible motive. Once admitted, no further explanation, medical or legal, was required. In Eigen’s words, ‘the crime was the disease. To accept the diagnosis was to find the actions of the accused without criminal intention.’

The underlying science emerged from a new generation of neurologists and brain specialists, of whom the doyen was Henry Maudsley. Maudsley drew on Darwin’s ideas of biological inheritance and on anatomical studies of the asylum population to formulate a model of mental pathology in which metaphysical concepts such as consciousness and will had no place. He maintained that in cases where the nervous system was weakened by an inherited pathology, criminal and violent instincts were irresistible: the ‘body becomes an organic machine set in destructive motion by a morbid cause’.

Maudsley’s theories short-circuited judicial argument even more cleanly than Prichard’s moral insanity had. By their logic any notions of delusion, intention or knowing right from wrong were irrelevant. In his writings Maudsley scorned the antiquated machinery of the law and dismissed the jury as ‘a singularly incompetent tribunal’ which had been falsely instructed that ‘insanity is a fact to be determined by any dozen of ordinary men.’ The feeling was mutual. On Maudsley’s rare appearances in court he was easily tripped into contradicting himself. He had written frequently of homicidal mania as a disease in its own right, but under cross-examination retreated to weaker claims that it was a symptom of more broadly accepted diagnoses such as melancholia or epilepsy.

Homicidal mania comprehensively failed the judge-jury test invoked by Eigen for moral insanity, yet during the late 19th century it was deployed by dozens of medical witnesses in response to an increase in apparently motiveless or senseless crimes. Eigen accounts for this by invoking a wider cultural context. The diagnosis dovetailed with new anxieties about a criminal class which propagated through both legal and medical opinion and the jury population. Measures such as the Habitual Criminals Act, passed in 1869 by a Liberal administration, indicate the strength of popular consensus that a minority of recidivist social deviants was responsible for the majority of crimes. Criminologists such as Cesare Lombroso popularised the idea that these were a biologically distinct race of ‘born criminals’, a type that overlapped with the congenitally insane and were, as one medical witness described them at the Old Bailey, ‘unable to resist the animal part of the functions of the brain’. Maudsley’s arguments may have fallen flat in court but his books on the subject, such as Responsibility in Mental Disease (1874), shaped the intellectual climate in which judges and juries operated. Once rising levels of vice and crime were attributed to a degenerate and incorrigible sub-population, the requirement to identify a relevant delusion in each case as stipulated by the rules was more readily sidestepped by a diagnosis that identified the accused as a member of a class to whom questions of guilt and intention were believed not to apply. Homicidal mania recast the question as ‘what, not who, had been responsible for the outrageous crime’.

The leading jurist James Fitzjames Stephen, considering the use of irresistible impulse as a defence in 1855, remarked: ‘There may have been many instances of irresistible impulses of this kind, although I fear there is a disposition to confound them with unresisted impulses.’ As Eigen observes, psychiatry is ‘the most culturally informed of medical specialities’ and as such the distinction between irresistible and unresisted is impossible to fix. Juries, by the same token, ‘recorded shifting ideas about volition and unrestrainable impulses’ that tracked changing assumptions about how far an individual’s behaviour was wilful or chosen and how far they could be expected to control it.

Why do people commit crimes for which there is no rational motive? The first question to answer is perhaps the one posed by the judge in the 1840 trial of Edward Oxford, with which Eigen closed Witnessing Insanity. When asked why he had fired a pistol at Queen Victoria’s carriage as she was taking her evening drive to Constitution Hill, Oxford could only muster: ‘Oh, I might as well shoot at her as anybody else.’ At the Old Bailey, after the leading medical experts of the day had duelled over moral insanity, delusions, phrenology and lesions of the will, Chief Justice Denman wearily inquired of the final witness, Dr William Chowne of Charing Cross Hospital: ‘Do you conceive this is really a medical question at all?’