Organisation of the judicial system

In contrast to most EU member states, the UK is a common law country and operates an adversarial system (where two advocates represent their parties' positions before an impartial person or group of people, usually a judge or jury, who attempt to determine the truth of the case). It is therefore an important feature of the UK's criminal justice system that the police, prosecutors and judiciary operate independently of each other.


The police are responsible for investigating allegations of criminal conduct by obtaining the relevant evidence. The police are independent in this regard; a prosecutor or judge cannot control or influence a police investigation. Once all of the evidence has been collected, the role of deciding whether or not to charge the suspect is a matter for the the police officer or the prosecutor depending on the nature of the crime (charging decisions). If the suspect is charged, the case is then transferred to a prosecutor who will attempt to convict the defendant.


Once the case has been transferred to a prosecutor, the prosecutor will decide whether the case is suitable for prosecution. The prosecutor will assess whether the case is in the public interest and whether there is enough evidence to provide a 'realistic prospect of conviction' against the defendant.

If the case is suitable for prosecution, the prosecutor is responsible for bringing the case to court and for advocating to the judge or jury that the defendant is guilty. The defendant will be provided with his own lawyer to advocate that the defendant is not guilty. The judge or jury will then determine where they think the truth lies.


When the case is before court, it is for the judge (or in more serious cases, a jury), to decide whether the accused is guilty or not guilty.

Judicial systems in Member States - England and Wales (e-Justice website)

Judicial cooperation

General description of the national system for international judicial cooperation in criminal matters

In the UK the judge also has a role to play when MLA requests for coercive measures are received, such as search and seizure requests. These measures are very intrusive, so when such a request is acceded to by the UK, the police are obliged by statute to apply to a judge for a warrant. The judge then considers whether all the statutory conditions for such a warrant have been met.

In MLA, once the request has been acceded to by one of the central authorities, it is often referred to the police as an "executing authority" to ensure that the request for evidence is executed.

Central Authority

MLA requests to the UK must be sent to a central authority. The central authority decides whether or not to accede to an incoming request for assistance and is also able to direct the police to obtain the relevant evidence. However, it is for the police to use their resources as they see fit, so for example, they are responsible for prioritising international requests for assistance alongside their domestic investigations. The central authority is not able to determine the priority of police work.

The UK has three central authorities:

UK Central Authority (UKCA)
Crown Office
Her Majesty's Revenue and Customs (HMRC)

All MLA requests relating to Scotland must be sent to the Crown Office.

All MLA requests to England, Wales and Northern Ireland relating to tax and fiscal customs matters should be sent to HMRC.

All other MLA requests for England, Wales and Northern Ireland should be sent to the UKCA (based at the Home Office). For full guidance on sending requests to the UKCA see MLA guidelines for foreign authorities (also translated into TurkishPolishSpanishFrench and Portuguese) and the new UKCA Online Submission Form.

The UKCA encourages requests by email, via secure channels of communication, to

For requests relating to road traffic offences only, contact

For requests relating to asset forfeiture and confiscation only, contact

For requests relating to atrocity or war crimes only, contact:

The UKCA can provide a secure Egress link to enable transmission of electronic documents to the UKCA which cannot be emailed. Please see our guides to using Egress: Egress Instruction Guide (PDF, 285 KB, 3 pages) and Your guide to the Egress file sharing platform.

Where sending requests by email or through a secure Egress link is not possible, and if physical transmission is necessary, requests can be sent to the following postal address, ensuring these are clearly marked as Asset Forfeiture and Confiscation, Road Traffic Offences, War Crimes or MLA, as applicable:

UK Central Authority
Public Safety Group
Home Office
6th Floor, Fry Building
2 Marsham Street

EU Member States are able to exchange criminal record information directly with the United Kingdom via the UK’s Criminal Record Information System UK-CRIS.

Part 3 Title IX of the EU-UK Trade and Cooperation Agreement provides for the exchange of criminal records data between the UK and individual EU Member States through a shared infrastructure, supplementing Articles 13 and 22(2) of the European Convention on Mutual Assistance in Criminal Matters 1959, and its Additional Protocols. The arrangements include streamlined and time-limited processes for exchanging criminal records information and specify that information can be exchanged for crime prevention and safeguarding purposes.

EU Member States should request court certificates directly from the relevant court. A copy of the criminal record (see above) must be attached to the request, which will also contain the name of the sentencing court.

Crown Dependencies and Overseas Territories

The Crown Dependencies (Bailiwicks' of Guernsey and Jersey, and the Isle of Man), and the UK Overseas Territories (Anguilla, Bermuda, British Virgin Islands, Cayman Islands, Falklands, Gibraltar, Montserrat, St Helena, Turks and Caicos Islands, and Pitcairn) are not part of the UK. The Crown Dependencies and the Overseas Territories are wholly responsible for executing requests within their own jurisdictions. Requests should usually be sent to the Attorney General of the Crown Dependency or Overseas Territory from where assistance is required.

Further Information

As of 1 January 2021, the new rules for the judicial cooperation between the European Union and the United Kingdom applies since parties agreed on the Trade and Cooperation Agreement between the European Union and the European Atomic Energy Community, of the one part, and the United Kingdom of Great Britain and Northern Ireland (hereinafter – the Trade and Cooperation Agreement).

With due respect to the regulation of data protection, the Trade and Cooperation Agreement provides a new legal basis, as well as makes references to the existing legal framework that covers wide range of judicial cooperation, such as:

·        surrender;

·        mutual legal assistance;

·        exchange of criminal records;

·        freezing and confiscation.

Find the following letters of the UK Central Authority to EU Partners: 

While UK Atlas is under maintenance, please check the Summary of the UK competent authorities for the contact details.

In the special section of the Judicial Library you will find:

  • the text of the Trade and Cooperation Agreement (in all EU languages);
  • forms for Surrender and Freezing and Confiscation (in all EU languages). Due to technical reasons, mistakes might have appeared in the text during the conversion from .pdf to .doc file, therefore we advise you to check the forms in the relevant text of the Trade and Cooperation Agreement;
  • notification from the EU regarding EPPO;
  • notifications from the EU Member States regarding competent authorities;
  • other Brexit-related documents.

The Brexit section of the Judicial Library will be updated on a regular basis.

The practical information for foreign authorities can be found on the website, including the MLA guidelines for foreign authorities (also translated into TurkishPolishSpanishFrench and Portuguese).

Links to UK guidance

Links to some sections of the EJN website

Links to the relevant sections of the Council of Europe and United Nations Treaties Offices websites containing information on the conventions to which UK is party

Information on the organisation of the EJN

The UK’s EJN structure includes 21 members. There are two contact points at the UK Central Authority (Home office). The other contact points represent the following organisations:

  • Crown Prosecution Service
  • Serious Fraud Office
  • Crown Office and Procurator Fiscal Service (Edinburgh)
  • HM Revenue & Customs
  • Public Prosecution Service Northern Ireland
  • The Law Officer Dept - Attorney General for Jersey
  • HM Attorney General's Chambers for Guernsey
  • HM Attorney General's Chambers for Isle of Man
  • HM Government of Gibraltar
  • UK Liaison Magistrate to Italy - Ministerio della Giustizia
  • UK Liaison Magistrate to Spain
  • UK Liaison Magistrate to France - Ministère de la Justice
  • UK Liaison Prosecutor to Poland

Useful national links