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Howard League for Penal Reform: Parmoor Lecture


Thank you for inviting me this evening, I am honoured to follow a long line of distinguished speakers, several of them friends of mine, and all of us admirers of the Howard League.

In preparation for this evening I watched some of the videos of previous lectures. Introducing last year’s lecture, your Chief Executive Frances Crook captured the work of the Howard League ever since 1866 with these words ‘What do we do with people who transgress?’

Taking that lead, I aim to be clear this evening about my role as the nation’s chief prosecutor, on behalf of the CPS which I lead. At a time of national upheaval and some political uncertainty, the role of a properly-funded and fully independent prosecution authority is absolutely pivotal.

The message to everyone in England & Wales, for whom the CPS is responsible, must be this: if you are the victim of crime, or a witness to any crime, you should expect and receive every assistance in being able to come to court to give your evidence.

We need to be equally clear towards anyone who commits a crime, in other words who broke the criminal law and who meant to do it. Anyone in that position must expect investigation followed by prosecution in court. We will play our part to ensure that you have full participation in the case, and if you are convicted at the end of it you should expect the punishment to fit the crime.

So those are the initial headlines. I will return to the role of the CPS in a moment. But first, to return to Frances’ words, what about people who transgress or are transgressed against, but who have what I will start by calling mental health issues? How do we deal with those cases, and are we getting it right? Are the right cases entering the criminal justice system, are they being dealt with fairly and effectively, and are they leading to appropriate outcomes – whether that be punishment or treatment?

So, the subject I want to talk about tonight is mental health and the criminal justice system.

Why? Well:

  • One in four adults and one in 10 children experience mental illness;
  • Our own research at the CPS, conducted in 2017, suggests that almost one in five of our cases involved a victim, witness or defendant with a mental health condition; and
  • It is estimated that 76% of female and 40% of male remand prisoners have a common mental health condition, as do 29% of those serving community sentences.
    • The higher prevalence amongst female offenders may be because many have experienced trauma prior to offending. For example: almost 60% of female offenders have experienced domestic abuse.
  • And we know from the Lammy Review that black and ethnic minorities are disproportionately represented in the criminal justice system and many arrive carrying a legacy of disparities from other services. The 2007 Healthcare Commission Census found that BAME groups are 40% more likely than white Britons to access mental health services via a criminal justice pathway.

So it is clear: mental health conditions are prevalent in our criminal justice system, but from a legal standpoint, how well equipped are we to deal with that?

Our common law and Article 6 of the European Convention on Human Rights protect the right to a fair trial. Are we confident that people with mental health conditions are able to participate fairly in the criminal justice system? And does the system lead to just outcomes?

These are questions I plan to look at tonight.

They are vital because recognising underlying mental health problems and addressing them through robust provision and pathways plays a significant role in improving health and justice outcomes for the individual, as well as the wider community.

The CPS represents the public interest in the criminal justice system, which includes considering the needs of victims, witnesses, defendants and our diverse communities. As I hope I made clear at the very start, we take our responsibility to support victims and witnesses with mental health conditions very seriously indeed.

Participating in our court system can be extremely difficult, and it is vital that we do all we can to minimise the impact on people who may find it especially challenging. This also means putting in place the necessary support to enable people to give their best evidence. Today, the CPS has published updated legal guidance which reaffirms our commitments to victims and witnesses.

However, tonight I want to focus on defendants with mental health conditions.

The Role of the CPS

As I’m giving this lecture as the Director of Public Prosecutions, I should start by explaining the role of the CPS in deciding whether or not to prosecute cases, especially those where there are concerns around the mental health of a suspect.

The Crown Prosecution Service is at the heart of the criminal justice system in England and Wales, working with our partners to protect the public and create a safe society.

Our work is demand led; we do not investigate crime, or choose which cases to consider. CPS prosecutors must review every case referred to us by the police, or other investigators. We provide expert legal advice early in investigations to help build strong cases, or identify where a suspect should not be charged.

Our core function is to ensure the right person is charged for the right offence, where there is sufficient evidence and where it is in the public interest. In this sense, the CPS is the gatekeeper to the criminal justice system.

We also play a broader role in upholding the rule of the law, working with our partners across the criminal justice system to ensure all defendants have access to justice and a fair trial.

So what does our role mean in relation to mental health?

We provide expert advice to investigators to help build strong cases

It is important to take a suspect’s mental health into account when making a charging decision. However, there are cases where it is necessary that a person enters the criminal justice system when their mental health condition is not known.

A suspect may, for instance, have been arrested after attacking someone violently. They may refuse to be assessed in custody or to engage with the police. They may have a mental health condition – or they may not. It is not possible to establish the situation: they cannot be compelled to undergo an assessment.

In this example, where there has been a violent physical attack, the case is sufficiently serious to merit an immediate CPS charging decision. In the course of the prosecution of the case the issue of the defendant’s mental health is explored, and we will work closely with the police and the defence to ensure this is done at the earliest opportunity.

There is every reason, however, why they are before a court. So we cannot always delay.

We identify where a suspect should not be charged

In other cases the CPS will act as a gatekeeper. These are likely to be cases of a less serious nature.

For example, a suspect is arrested for a public order offence, making offensive comments in a crowded market. The CPS and the police work together to understand that the suspect has recently been released from treatment. The police access information from health professionals, the liaison and diversion services, the defendant themselves or the family of the defendant. I must emphasise here that we, as a Service, depend on the police for this information, which will inform our decisions.

To continue with my hypothetical example, an assessment while in custody suggests a relapse and that further treatment is appropriate. Rather than introduce the suspect into the criminal justice system, the CPS may take the decision that the public interest, and the interests of the person in custody, are better served by ensuring the suspect undergoes this further treatment. Diverting cases like this can provide a more effective way to provide treatment and ongoing support, and to reduce the chance of future offending –-benefitting both the individual and the community. This approach is something we provide advice on in our guidance for our prosecutors.

When thinking about mental health and these decisions we have to make as gatekeeper, we must consider the current context.


Over recent years, our understanding of mental health has advanced significantly. You will no doubt have seen more and more people speaking out about mental health, whether it is sports people or actors sharing their experiences, the questions around the support provided to reality TV stars and talk show participants, or the high profile campaigns such as Every Mind Matters launched just last week.

Awareness is increasing and society is starting to break down some of the long-held taboos and stigma surrounding mental health. This is a positive and welcome step.

You may also have seen that today’s Queen’s Speech confirms that this government will continue work to reform the Mental Health Act ‘to improve respect for, and care of, those receiving treatment’.

Within the CPS we’ve been looking at mental health from two angles; the guidance we provide to prosecutors for our casework, and how we support the mental wellbeing of all our staff.

On a daily basis, CPS staff are faced with details of abhorrent crimes and it is important we provide them with the right support - in dealing with this or with other mental health issues they may experience. We have trained 271 mental health first aiders across the service - who can provide first-port-of-call support. We also provide access to telephone counselling, and have bespoke arrangements for those dealing with our most distressing caseload.

We, as a society and as a service, are changing and we are recognising the importance of mental health as well as physical health.

But criminal justice has not adapted. It has not moved forward with us. It is stigmatising and it is in need of change.

New CPS guidance

The CPS recently held a public consultation on our legal guidance for prosecutors, specifically including defendants with mental health conditions and disorders.

It was important because our guidance was out of step with the significant changes in understanding and attitudes towards mental health. Even the title of ‘Mentally Disordered Offenders’ felt uncomfortably dated.

We spoke to experts and listened to their advice. We also spoke to prosecutors about the practical challenges they face when prosecuting defendants with mental health conditions to develop the new legal guidance published today.  

New ways of thinking about disability have directed our approach - including the shift from the medical model of disability to the social model. The medical model links a disability to an individual's physical body. It supposes that a disability will reduce an individual's quality of life and that, with medical intervention, this disability will be diminished or corrected.

In contrast, the social model says that it is society that disables people, not their impairments. It is the way society is organised, rather than something inherent about people or their impairments, that disables and disadvantages them - whether that’s inaccessible court rooms or stigmatising attitudes and assumptions.

This is an attitudinal shift to recognise that an impairment or disorder, including a mental health disorder, doesn’t in and of itself have to disable someone’s access to justice.

Other important changes to the guidance include:

  • Emphasising the importance of full participation wherever possible, including through special measures for witnesses and other reasonable adjustments for defendants;
  • Providing prosecutors with additional support on information available at the time of charge  to avoid unnecessary delays; and
  • Providing more information on how to manage cases better, for example how to commission psychiatric reports on defendants to contribute to decisions about the case.

This is intended to be clear, practical guidance that will assist prosecutors to manage these cases fairly and effectively.

Other work on mental health in the CJS

And we are not the only ones in the criminal justice system improving our work in this area:

  • the Sentencing Council, of which I am a serving member, has consulted on its overarching principles for sentencing offenders with mental health conditions and disorders.
  • The Equality and Human Rights Commission is conducting an inquiry into adjustments that are made for defendants with cognitive impairments, mental health conditions and/or neuro-diverse conditions. The CPS has worked with the Commission on this inquiry and they have interviewed a number of our specialist prosecutors and policy leads.

As DPP, I am proud of the changes we are making, and that we reflect the advances in our societal approach to and understanding of mental health. I am proud that we are providing the right level of support to our prosecutors dealing with these tricky issues day in, day out.

We have listened to experts and we have listened to our prosecutors. We can play our part - update our guidance and practice, and make sure that we do not refer to ‘mentally disordered offenders’, but the simple fact that the law still uses outdated terms such as ‘lunatics’ (Trial of Lunatics Act 1883) is one clear sign this isn’t just about policy and practice, it is about bringing our legislation up to date.


There are two key issues I think need to be addressed - participation, also known as fitness to plead, and insanity. Fitness to plead relates to the defendant’s mental state at the time of trial, whereas insanity relates to their mental state at the time of the offence.


Let’s take participation and fitness to plead first.

It is an important part of our criminal justice system that a defendant has the right and the opportunity to contest his or her guilt by challenging the prosecution case in a full criminal trial. Finding someone unfit to plead means that they are deemed unable to participate in such a trial. This is a big decision with considerable implications for that person.

We would therefore expect it to be made on firm foundations. Indeed, I think we could agree some principles which should underpin it. I’ve tried to identify what they would be:

  • First - every effort should be made to facilitate a defendant’s full participation in a trial.
  • Second - there should be a coherent, modern definition of what not being able to participate in criminal proceedings means.
  • Third - a person who is to be subject to criminal proceedings in which they cannot participate should be in no worse position than those who are able to participate.

As I mentioned earlier, our new guidance published today aims to help deliver on that first principle – to facilitate participation. The second and third principles are relevant to the two particular points I want to cover now:

  1. The definition and determination of whether someone is fit to plead
  2. The issue of Mens Rea, also called the mental element of an offence - what was in a suspect’s mind at the time of a criminal offence.

1. The definition and determination of whether someone is unfit to plead

I’m going to discuss the Crown Court here - because strictly speaking fitness to plead only applies there. The position in the magistrates’ and youth court is less clear - that in itself is an issue. I think a serious issue - given the gravity of some of the offending which is actually tried in our 21st century youth courts there should be a procedure to better address fitness to plead in these courts.

In the Crown Court then, it is for the judge to determine if someone is unfit to plead - they do so on the evidence of at least two registered medical practitioners.

If someone is deemed unfit to plead, a finding of facts may follow - the jury determines the question of whether the defendant did the act alleged. The aim of the hearing is to test the evidence rather than to hold the defendant to account.

As a result of that hearing the defendant:

  • can be found not to have done the act and is therefore acquitted;
  • can be found to have done the act and:
    • receive an absolute discharge;
    • receive a supervision order for treatment within the community; or
    • receive a hospital order for treatment, which also means a loss of liberty.

The starting point for approaching fitness to plead is found in the Pritchard criteria, based on a case from 1836. More than a century later the Criminal Procedure and Insanity Act 1964 and case law set out the process and procedure in the Crown Court which allows for findings of unfitness.

These focus very much on specific tasks a defendant faces in a trial - whether they can:
1)    understand the charges;
2)    decide whether to plead guilty or not;
3)    exercise the right to challenge jurors;
4)    instruct solicitors and counsel;
5)    follow the course of the proceedings; and
6)    give evidence.
These are vital procedural steps in a Crown Court trial. But let’s contrast this list to the approach taken in civil law.

The Mental Capacity Act 2005 governs decision-making on behalf of adults who have either lost mental capacity at some point in their lives, for example as a result of dementia or brain injury, or where the condition has been present since birth.

It states that a person is unable to make a decision for himself if he is unable:
a)    to understand the information relevant to the decision;
b)    to retain that information;
c)    to use or weigh that information as part of the process of making the decision; or
d)    to communicate his decision (whether by talking, using sign language or any other means).

So here, instead of looking at tasks to be completed, we have a modern understanding of someone’s cognitive capacity - to support a modern understanding of what it means to fully participate in proceedings.

In their report on Unfitness to Plead, published in 2016, the Law Commission said the difference in these definitions ‘creates the potential for seemingly conflicting assessments of the same individual who, for example, could be found fit to plead in relation to a murder allegation, but lacking in capacity for litigation about the less critical issues of an inheritance dispute’.

This suggests we may not be meeting our second principle of basing decisions on a coherent, modern definition.

As the Law Commission put it: ‘the law aims to balance the rights of the vulnerable defendant with the interests of those affected by an alleged offence and the need to protect the public’. If we are failing to provide for full participation in criminal proceedings for all, or as nearly all as can be, then I fear we are not getting the balance right.

2. Mens Rea

Returning to what happens if someone is deemed unfit to plead in the Crown Court. As I mentioned, there may be a finding of fact, without consideration of the mental element of the crime.

Mens rea means the intention or knowledge of wrongdoing - what was in the mind of the suspect at the time of the offence. Mens rea is distinct from whether or not the individual committed the act itself.

In a standard trial, in order to prove that a suspect is guilty of a criminal offence, the prosecution must often prove that the suspect had a particular mens rea when committing the offence: for example, intention, or recklessness.

If a suspect is not fit to plead, then there will be no consideration of what was in their mind at the time of the offence. By focusing solely on whether the defendant carried out the act, there is a risk of putting someone in a worse position than someone who is fit to plead. And that is the 3rd principle I identified earlier.

In a standard trial consideration of mens rea could be something that leads to an acquittal - if the prosecution can’t prove for example that the suspect ‘intended’ to commit the offence, or was ‘reckless’ to the consequences, then they can be acquitted. They may have physically done the act, but if the mental element isn’t there, they are not guilty.

In other cases an individual may be convicted of an offence but evidence of mens rea may provide some mitigation for the purpose of sentencing.

This kind of consideration is not available to someone who is unfit to plead.

I will give you a short case example to demonstrate how this may disadvantage someone:

The defendant is out on a Friday night, drinking with his friends. He gets into an argument with a stranger about football, throws a punch and breaks the stranger’s jaw.

If this defendant is considered fit to plead, his mens rea will be considered i.e. what were his intentions at the time of the offence?

This can have a huge impact for our defendant and will decide what offence he is charged with. Let’s look at the two possible options for charging:

  • He could be charged with the offence of inflicting grievous bodily harm, contrary to section 20 of the Offences Against the Person Act 1861.
  • The mental element to prove here is recklessness.
  • The maximum penalty is five years imprisonment.


  • He could be charged with section 18 of the same act which is causing grievous bodily harm with intent.
  • The mental element to prove here is that he meant to cause the other person significant harm - this ‘intention’ is much more serious than ‘recklessness’.
  • The maximum penalty is life.

So you can see, a consideration of whether or not our defendant intended to cause this level of harm, or was merely reckless to it, has a huge impact on his case and his potential penalty.

If this defendant was found unfit to plead, this consideration would not take place. The court may look at the serious harm caused to the victim and find the defendant committed the more serious offence. While he wouldn’t receive life in prison, this would be on his record when, had his mens rea been considered, he could have been found to have committed the less serious offence.

And when the court is considering what order to make, they will be considering this in light of the more serious offence.

Participation and the Law Commission

These points are underlined by the Law Commission. In their 2016 report, they stated that the Pritchard test is ‘not consistently understood or applied by clinicians, legal practitioners and the courts’. They recommended:

a modernised test for unfitness to plead, bringing it into line with today’s psychiatric and psychological thinking. The new test would look at the defendant’s decision-making capacity and ask whether the defendant is able to participate effectively in their trial.

I believe this would put us in a better position to meet the three principles I set out earlier.


Next I turn to the defence or plea of insanity. This is another area characterised by outdated and stigmatising terminology - this is clear from its very origin: the Trial of Lunatics Act 1883.

Again, it is important to reflect on the principles that should underpin any consideration of this issue.

  • First, that criminal law should punish wilful or deliberate wrongdoing.
  • Second, that there will be exceptional cases where a person’s medical condition may mean that they are not criminally responsible.
  • And third, that we need a coherent and modern definition to determine when that applies and what then happens.

In relation to insanity, I will cover two points:

  1. The M’Naghten criteria
  2. The issues relating to the term ‘disease of the mind’

1. The M’Naghten critera

Determining insanity is based on the case of M’Naghten - a well-known case in legal circles. Indeed, when head of my chambers prior to becoming DPP, a print of the M’Naghten trial hung on my wall for many years.

On 20 January 1843, Daniel M’Naghten attempted to kill the Prime Minister, Sir Robert Peel but instead shot and killed his secretary, Edward Drummond.

M’Naghten was found not guilty on the grounds of insanity. The verdict was controversial and was debated by the House of Lords, which required a panel of judges to answer questions concerning insanity in criminal law.

The answers to these questions became the M’Naghten rules or criteria which must be satisfied in order to establish a defence of ‘insanity’:

It must be clearly proved that, at the time of committing the act, the suspect was labouring under such a “defect of reason”, from a “disease of the mind” that the suspect did not know that what he was doing was ‘wrong’ or did not know the nature and quality of the act being done.

M’Naghten is an old case - 1843. As every other lawyer in the room will immediately reply - much of our case law and indeed legislation is old, and still fit for purpose. Indeed, the Offences Against the Person Act of 1861, to which I referred earlier, can still be used effectively today. And I have personally prosecuted cases in the 21st century using the Explosive Substances Act of 1883.

Old age does not necessarily make a law unhelpful or obsolete. But some laws stand the test of time better than others. Physical violence is, sadly, fairly timeless in its basic elements. But in 176 years our understanding of mental health - and our society’s approach to it - has surely advanced beyond recognition.

The M’Naghten criteria are not based on a modern view of mental health.

And a defendant can only be considered ‘insane’ by law where the M’Naghten criteria are met.

This means someone who has been diagnosed by experts as suffering a severe mental illness, but who does not meet the M’Naghten criteria, cannot be found not guilty due to insanity.

This results in very few people pursuing the special verdict of not guilty by reason of insanity. The Law Commission have also investigated this subject and in their 2013 discussion paper, found that there are only around 30 successful insanity pleas each year in the Crown Court.

In their 2017 report ‘Mental Health and Fair Trial’, the law reform and human rights organisation JUSTICE stated: ‘The defence is rarely used in practice, in some respects due to the difficulty posed in meeting its complicated criteria, the stigma attached to the defence and the limited disposals available’.

If the purpose of the criminal law is to punish those who wilfully do wrong, does the operation of the insanity defence mean we punish rather than compulsorily treat those who are not wilfully doing wrong?

2. A disease of the mind

The M’Naghten test requires the accused to be suffering from a “defect of reason from a disease of the mind”. The law has not limited the idea of “disease of the mind” to mental health conditions. Instead, it has adopted a distinction between whether the cause of the accused’s lack of control was due to an “internal factor” - related to the individual - or an “external factor” which has influenced their behaviour at that time.

Involuntary conduct caused by an “internal factor” is classed as insanity and that leads to the special verdict of not guilty by reason of insanity. This is a special type of acquittal but the judge must impose one of the following:

  • a hospital order with or without a restriction order - a restriction order is whether or not you are entitled to leave;
  • a supervision order - this enables treatment to be given to the defendant. It is non-punitive and intended to provide a framework for treatment; or  
  • an order for absolute discharge.    

Involuntary conduct caused by an “external factor” is classed as non-insane automatism, leading to a simple acquittal.

To show what this distinction may mean in practice, let’s take the real-life example of two defendants with diabetes - clearly not something we would consider a mental health condition, but a physical one - who commit a crime.

The first defendant, Hennessy, was an insulin-dependent diabetic charged in 1989 with taking a motor vehicle without consent. At the time of the offence, he had not taken insulin or eaten for a number of days and was therefore in a hyperglycaemic state. The trial ruled that his hyperglycaemic state was the result of an internal factor, and so the defence of non-insane automatism was not available. The judge ruled that the defence of insanity was available, at which point Hennessy changed his plea to guilty and was sentenced to a suspended jail term. Note that an individual has chosen to plead guilty rather than accept the label and consequences of being found insane.

In the second case, the defendant, Quick, was a nurse and accused of assaulting a patient in 1973. He stated that he had taken insulin as prescribed that morning, had drunk a quantity of spirits and had not eaten. He had no recollection of the assault and his condition was consistent with hypoglycaemia. On appeal it was ruled that the defence of non-insane automatism was available because the malfunctioning of the mind in his case was not due to a ‘disease of the mind’ but instead a transitory external factor - in this case insulin. His conviction was quashed.

It is difficult to see why two people with the same underlying condition (i.e. diabetes), which is regulated in the same way (i.e. insulin), should have such different outcomes.

This is important because Hennessy risks losing his liberty through a hospital order if he pleads insanity or, as happened, his guilty plea resulted in a suspended prison sentence. Quick on the other hand, was acquitted and free to go.

Lord Justice Hughes (as he then was, later Lord Hughes of Ombersley), in his judgment in the case of Coley in 2003, said that this distinction “can give rise to apparently strange results at the margin, and that any future rationalisation of the law of insanity must take into account the rules for disposal, which concerned the court in Hennessy as they do in practice in many cases in the Crown Court”.

I share that view. This can't be good enough, and it is time that we come together to find a better way.

Public safety

There is, though, arguably a reason for this distinction between internal and external factors. There is a clear public safety concern if someone’s ill health means that they may offend again.  In contrast, an external factor is not an underlying condition, it is a one-off incident - an example might be a swarm of bees that enters your car and causes you to crash. Unlikely events do occur, sometimes.

But looking at public safety, does that not lead us to question the disposals available to the court on both the verdicts of insanity and non-insane automatism and whether they are appropriate? As a reminder, in cases of non-insane automatism, the defendant is acquitted and the court has no power to impose conditions. In cases of insanity, it is the hospital order, supervision order or discharge. Our sentencing framework has adapted extensively in recent years, and in other cases there are options available which can assist in rehabilitation, or future crime prevention.

If we’re talking about public safety as a concern, are there not more appropriate disposals that should be available in these cases? In the case of driving offences, for example, would it not be more useful for the court to be able to disqualify someone from driving? Should drug treatment or community-based mental health treatment orders not be available?

Lastly, on this point, as a matter of common sense, is it right that we label someone with diabetes, or who has a condition which causes them to sleepwalk, as insane?

Insanity and the Law Commission

The Law Commission’s view is that ‘the law is out of step with medical understanding’ and that the ‘label ‘‘insanity’’ ‘is stigmatising and inaccurate’.

Their principal proposal is that the common law insanity defence should be abolished and replaced with a new statutory defence where someone is not criminally responsible by reason of a qualifying recognised medical condition.

The new defence would be available in relation to any criminal offence and would result in a new special verdict - ‘not criminally responsible by reason of a recognised medical condition’.

There would of course need to be public policy considerations as to which recognised medical conditions qualify, and what outcomes are available upon such a verdict, but I believe this would offer a significant improvement to the current ‘insanity’ defence, with all of its peculiarities.


I hope I have demonstrated that the criminal law has a long way to go if we are to be sure that those with mental health conditions who find themselves in the criminal justice system are being treated fairly, leading to outcomes which we as the general public expect, including conviction and punishment in all of the right cases. More needs to be done to assure ourselves that our system supports good decisions on whether a case should be taken through the criminal justice system, or diverted.
A just outcome is that those who intend to do wrong are punished, and those who cannot be held responsible for their actions are appropriately treated. As I have said, public safety must be a significant consideration.

I hope it is clear from everything I have said that I am not suggesting we should stop prosecuting people with mental health conditions. What we need to be doing is balancing our approach and ensuring that those with mental health conditions, and I’m including victims and witnesses here as well, are treated fairly and proportionately.

This is about encouraging the criminal justice system to engage in a debate which, for wider society, is already in full flow. It’s about making sure as many people as possible can participate in their court cases. It’s about fairness and the fundamental principles and purpose of the criminal justice system. And it’s about time.

Further reading

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