Post-Brexit cooperation in criminal justice

The EU provides tools for efficient police and judicial cooperation in criminal matters. But those instruments may no longer be available to the authorities if there is a hard Brexit.

European Arrest Warrant scheme

Adoption of the European Arrest Warrant (EAW) was a watershed moment in the development of the European system of extradition. It removed the political and administrative phases of decision-making, making it a judiciary-run system. There is no longer a need to weigh the evidence, as there is a presumption of a similar standard of due process. The courts must also adhere to the standards of the European Convention on Human Rights. The free movement of people within the EU involves a risk of criminals evading justice by moving to another member state. The EAW was a response to that issue, which proved to be successful.

The Withdrawal Agreement between the United Kingdom and the European Union provides that the status quo will be maintained until the end of the transition period (31 December 2020) if the process is initiated before the end of the period. Absent an agreement to the contrary, leaving the EU will mean the UK’s withdrawal from the EAW system. None of the available alternatives offers the same efficiency and convenience as the EAW, hence a no-deal Brexit is a serious threat to the future interaction between UK and EU law enforcement bodies. Going back to the 1957 European Convention on Extradition would mean that requests for extradition would have to be made through diplomatic channels. The convention also provides for more grounds on which extradition can be refused than under the EAW. Overall, requests would be subject to a longer and a much more complex process, making extraditions more cumbersome.

The ramifications of withdrawal from the EAW system are starting to be noticed, with countries like Germany, Austria and Slovenia already stating that they will not extradite their own nationals to the UK after the end of the transition period.

Slowing down in taking evidence abroad

Although the EAW is the most distinctive feature of the EU judicial cooperation in criminal matters, it is by no means the only one. Taking of evidence abroad is of equal importance in practice. Normally, cooperation is based on mutual treaties or reciprocity. But the EU has replaced the plethora of different instruments with a uniform scheme for taking evidence abroad, including evidence not yet in existence. The European Investigation Order (EIO) is a fairly new instrument and clearly still in the making. Yet it has already proved efficient and useful for defence and prosecution in criminal investigations and prosecutions. The simplified procedure has made foreign examination of witnesses or seizure of documents easier and quicker. With a no-deal Brexit it is uncertain how judicial cooperation would be conducted. Most likely it would fall back on multiple bilateral treaties. That would certainly slow the process and in many cases discourage taking evidence abroad.

Consequences of a hard Brexit for criminal intelligence

These days, tackling organised cross-border crime and terrorism requires the exchange of significant amounts of data, e.g. on criminal convictions, the movement of suspects, and the activity of terrorist groups. That exchange is made possible within the EU thanks to the common data protection scheme.

A hard Brexit would mean that the sharing of that data between law enforcement bodies of the UK and the EU would have to stop. Apparently, the framework for legal safeguards of data protection would be included in a free trade agreement, but the bone of contention is maintaining the UK’s commitment to the European Convention on Human Rights.

As pointed out by John Scarlett, former head of MI6, the lack of a deal on security cooperation would render UK law enforcement weakened and vulnerable. On the other hand, the fate of data originating from the UK but stored in EU databases, in the event of a hard Brexit, remains an open question.

One of the databases the UK is now risking losing access to is the European Criminal Records Information System (ECRIS), used several thousand times every week for exchange of criminal records between member states. Another significant one is the Second Generation Schengen Information System (SIS II), which provides real-time alerts about individuals and objects of interest to EU law enforcement agencies. Given the popularity of air travel, we cannot ignore the Advance Passenger Information (API) system, storing such data as each passenger’s name, date of birth, nationality and passport number. API data are used to allow early identification of persons of known interest for security, immigration, customs or law enforcement purposes. The Passenger Name Record (PNR) contains other information held by the carrier, for instance how travel was booked and for whom, contact details, and travel itinerary. The PNR offers data for flights entering or departing the EU, and also on selected intra-EU flights. ECRIS, SIS II, API, PNR and other databases help facilitate cooperation for law enforcement and border control purposes. They also expedite and simplify tackling terror threats from across the EU, tracking them as they travel around Europe.


Even though it seems to be in the national interest for the UK to participate in the European Arrest Warrant and European Investigation Order schemes and the data-sharing platforms, pursuing a bespoke solution for the UK and seeking access to the full suite of tools will be a challenge for negotiators.

It appears from the European Commission’s stance during the Brexit deal negotiations that unless the UK has a standard of data protection equivalent to the EU’s, the UK will not have access to the EU databases. If the UK were to lose access to the EU law enforcement databases and data-sharing platforms, the data currently available in seconds could take weeks to retrieve, abruptly and seriously interfering with the UK’s policing activities.

Łukasz Lasek, adwokat, Business Crime practice, Dispute Resolution & Arbitration practice, Common Law Desk, Wardyński & Partners