PACE For Beginners – Part 3

This is the third in a series of posts explicating the vagaries of the Police and Criminal Evidence Act 1984 (PACE) – Part One covered the general legal basis of detention in custody, the timescales for detention without charge and general principles around clinical risks and vulnerable people; Part Two covered certain specifics that will relate to many or some detainees, depending on the legal nature of their detention, including legal rights, searches, samples, reviews, decision to charge and so on. This third installment attempts to highlight how all of that relates to decisions by mental health professionals who come in to police custody at various stages and specifically to Mental Health Act (MHA) processes which often need to run in parallel to PACE.

Three things tend to be going on where detainees are in police custody interfacing with considerations under the MHA –

  • Detention in police custody as a Place of Safety – for those detained by officers under ss135 or 136 of the Act in order to allow assessment by an AMHP and a Registered Medical Practitioner to determine any necessary arrangements for treatment or care.
  • Detention in police custody for other, rare MHA reasons – sections 18, 42 and 55 of the Act are all infrequent situations where police officers have been called upon to detain individuals as something of a staging post until other health processes can take effect. Detention in custody is far from ideal here, but has been known to happen.
  • Arrests for non-MHA reasons where assessment under the Act is required – this would be for potential admission to hospital and this is the area on which most needs to be said so see PACE versus MHA, below.

The first two are relatively straight forward to interface with PACE, because they are touched by PACE only in terms of the standards of legal rights and medical welfare that are expected whilst a person is in custody. Code C of the Codes of Practice to PACE apply to those detained in police custody who are there for reasons connected to the Mental Health Act, but the whole rigmarole of section 37 of PACE, section 34 of PACE, reviews of detention and relevant times simply do not apply. Individuals are detained in police custody for up to 72hrs where ss135/6 have been used; and until necessary arrangements are made in the other cases.


It is where people were originally arrested for alleged offences that things get complicated! MHA considerations can be introduced at any stage after arrest depending on a huge number of uncontrollable variables. Arresting officers may have information or observation that mean they directly inform the custody officer of mental health concerns at the start of a process. Arresting or custody officers may form their own view about someone’s condition based on their observation of someone’s behaviour in first hour or so. Depending upon the local arrangements there may be a Liaison and Diversion (L&D) service in custody where a mental health nurse is able to screen the detainee and gain access to local mental health trust records to check someone’s background. Irrespectively, the Force Medical Examiner or custody forensic nurse may identify reasons to raise concerns. Finally of course, information may come to light many hours in to detention from relatives of those detained or from solicitors who have attended the police station to represent suspects in interview.

So this means that considerations around mental health or Mental Health Act assessment may arise in two different legal contexts following arrest for an offence –

  • Detained by section 37 of PACE and sufficient evidence to charge – there tends to be evidence to charge at or shortly after arrival in custody for more straight-forward and often less-serious offences. Things like public order or drunkenness offences where two or more police officers have witnessed the conduct which forms the basis of the offence. Drinking-driving allegations are often settled quite quickly after arrival in custody because as soon as detention is authorised, the detainee is subject to a station-breath test and they either fail that or they don’t. It also doesn’t really matter for investigative purposes at what time the MH concerns become known.
  • Detained under s37 of PACE and insufficient evidence to charge – it is where criminal investigation is ongoing and the outcome not yet known that we start to see complications. For most of those detained in custody for an alleged offence, there is not enough evidence to charge on first arrival. If concerns about someone’s mental health become known early on and MHA assessment can occur rapidly enough within that overall 24hrs, there is little difficulty ensuring these two pieces of legislation interface effectively. It’s where there is delay in arranging assessment or delaying in accessing a bed that we really see the problems.

Of course, it is always worth remembering that the social assumptions underpinning our Mental Health Act were mainly formed in the 1950s, those that weren’t were formed in the 1980s when modern mental health legislation was introduced and then first reformed. In the 1950s, it just wasn’t anticipated that there would be what we would now call bed management problems and PACE didn’t exist – there was greater latitude for police officers to make processes work. In the twenty-first century we now have human rights law more directly governing what state actors are permitted to do and far greater liberal scrutiny over the impact of legislation. This is (at least partly) why we see problems. 


The principles of PACE outlined in Part One of these posts remains the legal system by which detention is governed notwithstanding that a Mental Health Act assessment has been requested. During whatever time it takes for an AMHP and two DRs to convene to assess, the custody officer remains bound by the ongoing requirement to determine whether the grounds for detention still exist and whether there is (yet) sufficient evidence to charge. If, for whatever reason, those grounds cease to exist whilst the MHA assessment is being arranged or whilst a bed is being sought for any admission that. Is thought necessary, then s34(2) of PACE applies.


So for example, imagine a man is arrested at 10pm in a fight at a pub. Arresting officers remove him to custody after the victim and two witnesses allege the offence during an argument. Another officer attends to the victim at the incident, going with him and paramedics to hospital for treatment to his injuries. Imagine that it takes a couple of hours for the victim to be sober enough to give a statement and he then chooses not to do so, telling the officers he doesn’t want anyone prosecuted. He then leaves the hospital and declines to be any further involved – only of the witnesses has given a statement. Meanwhile at the police station, the custody sergeant has flagged up concerns about the suspect’s mental health and the Force Medical Examiner has requested a MHA assessment which has not yet occured. If there was sufficient evidence from the arresting officers to justify detention for something other than the assault, he could be arrested in connection with the other matter and detained – perhaps there was also evidence of drunk and disorderly behaviour? If not, then s34(2) PACE seems to suggest that the basis of the original detention has ceased to apply and therefore the person should be released, either with or without bail. The MHA will have to happen in some other way.

Another example – this one is the most common type of problem and one which I estimate is happening a few thousands times a year in England and Wales. Imagine officers arrested a man for an offence who is then detained in custody pending investigation because there is insufficient evidence to charge. He was declared unfit for interview because of the need to assess him under the MHA and assessment indicates admission is required under s2 of the Mental Health Act. Imagine at the point where the custody officer is told the outcome of the MHA assessment, there is either insufficient evidence to charge or it is not in the public interest to do so because of it being a minor offence by a suspect with no previous convictions. If the PACE investigation is continuing, then s37 may still apply and detention may continue. If it has already concluded, then s34(2) applies and we start to see consideration of release, either with or without bail.

What happens next is the stuff of long debate: I’ve written about it elsewhere on the BLOG and I’ll refer you to those posts if you want more on it, in full acknowledgement that the law is ultimately both conflicted and vague. What I most usually say to police officers faced with these situations is you should just remind the AMHP and DR who led the. Assessment of sections 13 and 140 of the Act and remind them of Articles 3 and 5 of the European Convention on Human Rights. The 1983 Mental Health Act simply did not foresee a situation in which NHS Commissioners would commissioner fewer employees beds than were needed to ensure sufficient slack in the system to ensure a swift admission. Where the NHS continues to decline to make a bed available, officers should escalate to senior police officers like the duty superintendent or even a chief officer for support in resolving the situation. I’m sure we can all recall the case of the 16yr old girl in Devon from November 2014. Ultimately, if officers are acting reasonably and in good faith, they may potentially rely upon section 139 of the Mental Health Act to protect themselves from legal liabilities.


Just a few points on those detained in custody pending appearance at court and there are two situations – 

  • Arrested under the terms of a court warrant – there are various types of warrant and they impose different kinds of duties, but they are all basically to take someone before a court and it is usually the first available sitting after the arrest and transfer to custody. Of course, medical matters take priority over a legal appearance and if the need to undertake urgent assessment of someone’s health meant missing a court appearance, it is unlikely to be questioned. 
  • How many court appearances can you skip whilst keeping someone detained under a warrant that instructed the police to bring them to court?  If you need to divert someone to inpatient hospital care, you can inform the court of what happened and apply for the warrant to be reissued.
  • Arrested to prevent a Breach of the Peace or its continuance –  as with a warrant, the duty upon the police following an arrest in connection with a Breach of the Peace is to ensure the person appears before the first available court to be bound over to keep the peace. Again, delaying appearance for a sitting would be unlikely to be question if it allowed potentially serious health problems to be prioritised, but how many sittings can you miss and keep someone detained?
  • You will remember the case of a 16yr old girl in Devon in November 2014 – she was arrested on a Thursday evening for a Breach of the Peace and all things being equal, she would have appeared at court on Friday morning to be bound over. Failing that there are Magistrates on Friday afternoon and again on Saturday morning. Under what law you justify detention if no application had been made?

Part Four of this series offers some other detailed examples how PACE unfolds during a criminal investigation whilst mental health or Mental Health Act considerations emerge as relevant – it’s not critical to an understanding what’s above, but is set out different, so might make more sense to some who prefer bullet points to prose.paragraphs!

Winner of the President’s Medal,

the Royal College of Psychiatrists.

Winner of the Mind Digital Media Award


All opinions expressed are my own – they do not represent the views of any organisation.

(c) Michael Brown, 2019

I try to keep this blog up to date, but inevitably over time, amendments to the law as well as court rulings and other findings from inquests and complaints processes mean it is difficult to ensure all the articles and pages remain current.  Please ensure you check all legal issues in particular and take appropriate professional advice where necessary.

Government legislation website –

3 thoughts on “PACE For Beginners – Part 3

  1. Thank you for providing the PACE for Dummies Blog. As an AMHP student it has enabled me to appreciate the Police perspective and develop a better insight into the tensions existing between both Acts and have to work together to resolve these as best as possible. Really enjoyed your humour too, made the information easier to digest. Thank you

  2. There are alternative situations we often find working within a Crisis Team which interface with the ‘Pace Clock’ when use of the Mental Health Act is not requested or required.

    Where an individual is arrested for an offence, (the severity of which can vary wildly), and the FME is called to see the individual (presumably at the instigation of the custody sgt.).

    – The FME, often with no specialism in Mental Health, has concerns about the mental health of the individual and if the individual is asking for admission to hospital contacts the Crisis Team.
    -The FMEs, by experience, are aware that AMHPs will consider a request for an MHAA and determine that, where a patient is asking for admission, under the least restrictive principle, detention, and therefore a MHAA, is usually not warranted unless there is some information which indicates otherwise

    – The concerns of the FME about Mental Health may be because of their presenting symptoms, but these can often be complicated by substance and alcohol use and there is significant frustration from custody staff where the Crisis Team will refuse to assess until the effects of alcohol abate with frequent references to the PACE clock. Presumably alcohol intoxication would have to abate before someone is fit to be interviewed in any case?

    – Where a patient is known to a CMHT, a member of the CMHT would be expected to see the individual in the first instance, if they then thought an admission was required a referral would then be made for a Gatekeeping Assessment by the Crisis Team. By this time again it is not unusual for the PACE clock to be ticking very insistently.

    – Sometimes the FME will refer because the individual expresses distress and suicidal ideation and will state they will kill themselves if they go to prison or sometimes threaten the same if they are released. These alone are unlikely to be grounds to admit to a psychiatric hospital, but appear to leave the police or professionals in a very difficult situation often hoping things will resolve before the PACE clock expires. (from reading your blog this would seem to be bad practice).

    – The FME often defers making a decision about fitness to be interviewed until the individual has been assessed by Mental Health Professionals, even though they will be Nurses or Social Workers who are not trained or qualified to make that judgement. What are the guidelines for this? Perhaps another blog?

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