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The Role of The Crown Prosecution Service

The Crown Prosecution Service is the government department responsible for prosecuting criminal cases investigated by the police in England and Wales.

As the principal prosecuting authority in England and Wales, we are responsible for:

  • advising the police on cases for possible prosecution
  • reviewing cases submitted by the police
  • determining any charges in more serious or complex cases
  • preparing cases for court
  • presenting cases at court

Find out more about the role of the Crown Prosecution Service

Decision to Charge

Once the Police have completed their investigations, they will refer the case to the Crown Prosecution Service for advice on how to proceed. We will then make a decision on whether a suspect should be charged, and what that charge should be.

Find out more about private prosecutions

Decision in relation to the death of Olaseni Lewis


Olaseni Lewis died on 4 September 2010 following his restraint by a number of Metropolitan Police Service (MPS) officers at the Bethlem Royal Hospital, where he was, initially, a voluntary patient because of mental health problems. He was aged 23 at the time.

On 29 August 2010, Mr Lewis was taken by his parents to Croydon University Hospital where he was detained under section 136 of the Mental Health Act 1983. Mr Lewis was then taken to Maudsley Hospital but left during his assessment. The police were called and returned Mr Lewis to the hospital before he was later transferred to Bethlem Royal Hospital as a voluntary patient.

At the Bethlem, the evidence suggests that Mr Lewis became restless and was forcibly sedated by staff. However, this had no effect and he damaged a door attempting to get out of the hospital. Mr Lewis was sectioned before the police were called and were asked to assist in his restraint and removal to a seclusion room. Once there, Mr Lewis was restrained for a second time. Other officers were called to assist and were in the course of arranging to exit the room when Mr Lewis collapsed. He was transferred back to Croydon hospital where he died.

The Independent Police Complaints Commission (IPCC) referred the case to the Crown Prosecution Service (CPS) in August 2011 with a report which concluded there were no criminal suspects and that no criminality and no misconduct under police regulations had been identified. The report was withdrawn by the IPCC in October 2011 and was re-referred in June 2012 with the same findings. No one had been treated as a suspect, although the IPCC expressed concern over the length of the restraint. In February 2013, the IPCC reopened their investigation with a view to interviewing under caution those officers involved in the restraint. The MPS declined to allow their officers to be interviewed by the IPCC, arguing that a reinvestigation would be unlawful.

There then followed legal action in the civil courts where Mr Lewis' family succeeded, in September 2013, in having the original investigation quashed, allowing the IPCC to reinvestigate and interview under caution. The case and updated IPCC report were then re-referred to the CPS in 23 April 2015. The latest IPCC report concludes that a number of officers have a case to answer for non-criminal misconduct. No final recommendations are made in respect of criminal offences within the report but the IPCC referred the report to the CPS because it was of the view that the evidence outlined in the report may in the circumstances indicate offences of assault, misconduct in public office or manslaughter. It should be remembered that the threshold for a criminal prosecution is far higher than that of internal disciplinary proceedings.


Following very careful consideration of the evidence provided to us by the IPCC, the CPS has decided that there is insufficient evidence for a realistic prospect of a conviction against any of the police officers involved in Mr Lewis' restraint for any offence. Our consideration of the case included an external review by a Queen's Counsel which was concluded in early 2013. The additional material recently supplied by the IPCC has not changed the evidential position in relation to possible criminal charges. The decision was taken in accordance with the Code for Crown Prosecutors which requires there to be sufficient evidence for a realistic prospect of a conviction and a consideration of the public interest factors before charges can be authorised.

It should be noted that despite the reinvestigation launched in 2013, the bulk of the evidence has remained unaltered from that which was referred to us in 2012. The QC instructed by the CPS advised the IPCC on a number of points to be put to the police officers in interview but they invoked their right to silence (the right of every suspect) and did not answer questions, relying on prepared statements.

The offences that we have considered, and the reasons for taking no further action, are set out in turn below.

Actual Bodily Harm (ABH):

In law, police officers are entitled to restrain an individual until they have achieved control and are not required to run the risk of being assaulted.

The evidence suggests that at various points during the restraint of Mr Lewis, he was handcuffed, struck with a police baton and had his jaw held by a police officer. There was also an allegation, made by a member of the medical staff, that he was punched by an officer.

In deciding whether there is sufficient evidence that these alleged actions were criminal, the law requires us to consider the specific circumstances of the situation. The IPCC report suggests that officers arrived at the hospital having been warned that Mr Lewis was violent or posed a threat of violence and they could see the damage to a door frame allegedly caused by Mr Lewis. The majority of the accounts from hospital staff support the view that Mr Lewis was behaving aggressively.

As such, we consider there is insufficient evidence that the baton strikes, which left only superficial injury, and the handcuffing of Mr Lewis were unreasonable or unlawful in the circumstances and cannot be considered as amounting to the offence of assault occasioning ABH as defined by law. There is also insufficient evidence that the pressure to Mr Lewis' jaw caused any significant injury. Indeed, the evidence suggests that this was applied early on with a view to obtaining control over Mr Lewis. If this was the punch seen by the hospital staff member, it follows that no charge can result. Alternatively, if the punch was some other incident there is insufficient evidence to say who inflicted it.

Unlawful act manslaughter and Gross Negligence Manslaughter (GNM):

In relation to unlawful act manslaughter, we would need to demonstrate that the actions of the officers were unlawful in the circumstances. In order to prosecute an offence of GNM, we would need to demonstrate to the criminal standard that the way in which the officers restrained Mr Lewis was not necessary in the circumstances and therefore amounted to them breaching their duty of care towards him.

In considering these offences, it is important to remember that the law entitles officers to restrain an individual until they achieve control. Having carefully considered the evidence, including the views of a number of experts, we have concluded that there is insufficient evidence to show that the manner in which he was restrained was unlawful or unnecessary given the circumstances in which the officers found themselves. The evidence of the hospital staff does not, on the whole, criticise the methods as excessive and there is considerable evidence as to Mr Lewis' strength and violence.

Misconduct in a public office:

The offence of misconduct in public office has a high criminal threshold, far higher than the threshold required to bring internal disciplinary misconduct hearings. The severity refers to the initial act rather than any tragic outcome.

Whilst it may well be said that Mr Lewis' restraint might have been handled better, there is insufficient evidence that the actions of the officers meet the high criminal threshold required for this offence.


For the reasons set out above, we have advised the IPCC that no further criminal action should be taken in relation to this matter. The issue of whether to bring internal disciplinary proceedings, which do not require the same level of evidence, is a matter for the IPCC.

We understand that our decision will be hugely disappointing and frustrating for the family of Mr Lewis who have acted with dignity throughout this process. However, the CPS can only prosecute where there is sufficient evidence of an offence as defined by the law.

We also understand that the time taken to reach this decision has only added to the disappointment and frustration. We want to reassure Mr Lewis' family that we have reached this decision as swiftly as possible since receiving the IPCC's latest referral which was made in April of this year.

We have written to Mr Lewis' family to explain our decision in detail and to offer a meeting should they want one.


Notes to Editors

  1. For media enquiries call the CPS Press Office on 020 3357 0906; Out of Hours Pager 07699 781 926
  2. The CPS consists of 13 Areas in total, each headed by a Chief Crown Prosecutor (CCP). In addition, there are three national casework divisions: Specialist Fraud (formerly Central Fraud and Welfare, Rural & Health Divisions), Special Crime & Counter Terrorism and Organised Crime. CPS Direct is a 'virtual' 14th Area which provides charging decisions to all police forces and other investigators across England and Wales - it operates twenty-four hours, seven days a week, 365 days a year.
  3. At 31 March 2014 we employed a workforce of approximately 6237 staff (full time equivalent), including around 2226 prosecutors and 3629 caseworkers and administrators. Further information can be found on our website:
  4. The CPS, together with ACPO and media representatives, has developed a Protocol for the release of prosecution material to the media. This sets out the type of prosecution material that will normally be released, or considered for release, together with the factors we will take into account when considering requests. Read the Protocol for the release of prosecution material to the media.