Roger Sahota of this practice was recently asked to comment for a media outlet on the implications for the criminal justice system if the UK were to vote to leave the EU in the summer referendum.

In reality, BREXIT is unlikely to impact significantly on the UK criminal justice system. As with immigration, asylum and police cooperation matters, the UK is not bound by EU law in these areas but has an “opt in” arrangement which allows it to choose which EU provisions it subscribes to.

In December 2014 the UK government exercised its "opt in" prerogative (negotiated under Part 36 of the Treaty of the Functioning of the EU" to opt in to 35 "third pillar" EU measures. These “third pillar” measures are arrangements for police and judicial cooperation in the EU on criminal matters, recognised as part of EU law by the Treaty of Lisbon.

The 35 measures include the European Arrest Warrant (EAW) Framework. Other provisions include measures for the exchange of criminal records information and police intelligence and the recognition of financial penalties across Europe as well as the European Supervision Order – which is the subject of a another blog to be forthcoming.

For criminal lawyers, these measures are important in practice because they mean that it is now relatively easy for the authorities to obtain, for example, the previous convictions of an EU national in an admissible form for a bail application or to establish a video link with a witness elsewhere in Europe or to obtain evidence from another police force in the EU.

In conclusion, in the event of a success for the "vote leave" campaign in the upcoming referendum, it is unlikely that we will see any dramatic change in these arrangements.