Created 2 years ago, updated 5 days ago

The data used in the MPS Custody (Arrests, Disposals, Strip Searches) dashboard is available here Custody Dashboard | Tableau Public, along with the related data definitions. Please note that, this data set runs a month behind with monthly updates.


Date criteria is based on Date of Arrest as first recorded on the Custody Record.

A Custody Record is created when a person reaches a Custody Suite. Data contained only relates to Custody Records created in the Metropolitan Police Service Custody Suites.

The volumes show a Count of Custody Records and not a count of individual people. A person may have been arrested/ detained more than once in the periods being viewed.

The Officer Defined Ethnicity is recorded on the Custody Record and then grouped as shown for reporting purposes. At the request of the Mayors’ Office for Policing and Crime (MOPAC), the Detainee’s Self Defined Ethnicity is not used in this report.

Youth is defined as a detainee who is at least 10 years of age at the time of Arrest, and under the age of 18 at the time of Arrest.

The “First Arrest Offence” is the first reason for arrest given to the Custody Staff by the Arresting Officer and is usually the most serious matter. These have been grouped into broad terms for the purpose of reporting. It must be understood that the Detainee may be dealt with for more than once offence whist in Detention.

The demographic breakdown for the Custody Population may not be directly comparable to that of London. The arrested person may be from anywhere in the UK or abroad.

Also, due to Central Cell Allocation, even on a local level, a person arrested may not go to a Custody Suite local to the area they live or the area in which they were arrested.



Date criteria is based on Date of Arrest as first recorded on the Custody Record.

The volumes shown are based on a Count of Offences recorded on Custody Records.

Each Custody Record may have more than one offence recorded on it.

Each Offence is subject to its own Disposal.

Each Offence may be given different Disposals at different times. The current (latest) disposal is shown. This may not be the last/ final Disposal.

A Custody Record may have more than one similar offence recorded on it. Therefore, one Custody Record may have multiple similar offences each with its own/ different disposal.

Disposal Decisions are based on numerous factors. These may include (but not limited to)

-        Available evidence

-        Any admissions

-        Previous offending history

-        Willingness of victims/ witnesses to substantiate allegations, make statements etc.

-        Public arrest criteria


Strip Search

Date criteria is based on Date of Arrest as first recorded on the Custody Record.

The volumes shown are based on whether Strip Search was recorded as being undertaken at any point during the Detainee’s Detention.

The primary reason for a Strip Search being authorised/ conducted in a Custody Suite is to ensure the safety of the Detainee and the people around them. Factors effecting this consideration may be in relation to (but not limited to):

-        The nature of the offence(s) arrested for (hidden weapons or drugs)

-        Warning markers on the PNC (Police National Computer)

-        Concerns raised by responses to Risk Assessment questions.

Strip Search can be undertaken for any offence, but when looking at specific offences, is more likely to be authorised/ conducted for offences relating to drugs or weapons.

Detainees can be arrested for more than once offence.

The number of Detainee’s Strip Searched can be viewed by the following Offence Groups (and where a detainee has been arrested for one or more offences):

-        Drug offences

-        Drugs and other offences

-        Drugs, Weapons and other offences

-        Other offences

-        Weapons and other offences

The warning Markers on PNC may refer to the individual secreting items on previous occasions or has indications of self-harm/ attempted suicide. It goes without saying that such warning markers have significant impact on decision making with regard to authorising a strip search.

Any relevant warning markers on PNC are not recorded on the MPS Custody System in a way that allows data analysis. Therefore, one of the main factors in effecting the reasons for a strip search in not available and any conclusion drawn from the information displayed must take this into account.

When reviewing the demographic data in this dashboard it should first be remembered that this relates to the metropolitan custody detainee populations and not to any wider group.

When viewing the entire Custody Population there is initially a disproportionality in the percentages strip searched. However, when various offence groups are examined it will be seen that there is a significant disproportionality in the breakdown of arrests. Also, given that the details of any PNC warning markers are not available, then it follows that any proportionality issues may not be as unambiguous as may first appear. 

Due to an internal IT deployment, from 27th February these datasets may be temporarily disrupted. Work is ongoing to rebuild these datasets.