One of the many areas of law to be affected by Brexit is of course that of Police and Criminal Justice (PCJ). But it is worth considering not only what the impact of Brexit will be on practical issues such as extradition and police cooperation, but also what our existing experience in the PCJ sphere can tell us about the impact Brexit will have on our ability to negotiate with our EU counterparts in this area in future.

It’s worth noting at the outset that the UK has almost always had a looser relationship with Police and Criminal Justice measures in the EU than have other member states. It is true that we did sign up to the Schengen PCJ measures on police cooperation even though we were not signing up to the rest of Schengen removal of border controls. And of course we participated in the post-Maastricht ‘Pillar 3’, then known as Justice and Home Affairs, but the whole point of the three pillar structure was that while the first, EC pillar gave the EU much greater power, such as universal jurisdiction of the ECJ, enforcement powers on the part of the Commission and the use of qualified majority voting (removing the veto of individual states), the second and third pillars did not. And when the Treaty of Lisbon moved Police and Criminal Justice into the first pillar, with the associated increase in EU control, the UK chose to opt out of EU PCJ measures and then opted back into a narrower list of 35 measures.

So the first conclusion is that it seems fairly clear that whatever reasons there may have been for supporting Brexit, Police and Criminal Justice could not really have been one of them. The UK had already been given a great deal of flexibility and had taken a very à la carte approach to the measures available, opting in or out of each measure on an individual basis.

The areas we chose to opt back into include the European Arrest Warrant, mutual recognition of financial penalties, confiscation orders and asset freezing and recovery, evidence, measures relating to security at football matches, sharing of criminal records, internet child pornography etc and measures setting up EUROPOL and EUROJUST. In terms of what happens now, the situation is very similar to that applicable in other specific substantive areas of law.

Taking what the House of Lords Select Committee calls the ‘single most important’ PCJ measure, the European Arrest Warrant as an example, this has effect in English law through the Extradition Act 2003. So in technical terms because it is an Act of Parliament, that Act would obviously not cease to exist just because we were no longer members of the European Union, but of course in substantive terms the whole approach of the EAW and the whole existence of the 2003 Act is premised on a process of mutual recognition between Member States, and mutual extradition.

Just by way of background, for anyone not familiar with the workings of the EAW, the 2003 Act divides states for extradition purposes into category 1 and category 2. Category 1 states are the other EU member states and Gibraltar, category 2 are all the other states with whom we have extradition agreements which are not members of the EU. The difference is that for category 1 states, where the offence could lead to imprisonment of three years or more, as long as it is a ‘listed offence’ (i.e. one which appears on the Framework directive list), there is no requirement of dual criminality. In other words extradition can take place even if it is not an offence in the UK.  This is part of the EU’s approach of ‘mutual recognition’, which was chosen over that of unification or creation of a common corpus juris of criminal law, and it works both ways, leading to mutual recognition of both pro-prosecution rules like the arrest warrant and measures protecting the rights of the accused. So the reason one Member State will recognise warrants and permit extradition even in cases where there is no equivalent criminality in that state is because the state is also able to issue arrest warrants to other Member States who will recognise them in return. If the UK is no longer a member of the EU there is no guarantee that this reciprocity will continue to happen, in which case we would not necessarily wish to keep our end of the bargain either.

It is worth noting that this is also likely to have an impact on our relations with third states as well. So for example, in 2011 we opted into the 2009 Mutual Legal Assistance (MLA) agreement with Japan. This was the first free-standing EU-third country MLA agreement; previously it had been necessary for all 27 Member States to amend their existing bilateral treaties with third states, whereas the Japan agreement made it clear that it is now possible for EU member states to combine to reach one agreement. Another example is the EU’s agreement with Australia, the US and Canada on sharing of air passenger data. We will, post Brexit, have to negotiate and form such agreements on our own.

More generally, the options available to us in the light of Brexit are similar to those available in other substantive areas of law: either we negotiate some kind of on-going relationship with the EU which includes our current opt-in to the EU rules we like, or, outside any relationship we have with the EU we have to individually negotiate extradition and other PCJ agreements with each of the 27 Member States individually. However, the very fact that we have already been through the process of opting out of Lisbon and then opting back in again means that in the area of Criminal Justice it is a bit easier to predict what effects are likely to follow Brexit.

The first conclusion is that it does seem likely that the UK would want to preserve the measures we opted back into as much as possible, precisely because as a country we have already been through the arguments and decided that they are worth having. The Government’s own report into the UK/EU balance of competence on Criminal Justice in 2014, for example, stated that had it not been for the existence of Mutual Legal Assistance rules relating to evidence, it might not have been possible to convict Husein Osman, one of the failed July 21st bombers.

Second, it is clear from the opt-out and opt-back in again process post Lisbon that our concerns more generally about losing control over the formation of rules, even if we manage to retain their equivalents in outcome post-Brexit, are borne out by experience in the PCJ sphere. So, for example, the Law Society has argued that ‘it should also be borne in mind that, in not opting in, the UK loses its ability to influence in the development of EU instruments by proposing provisions which could benefit the UK as well as the entire EU criminal justice system’ while Europol has stated that ‘By sitting at the negotiating table, the UK has consistently demonstrated its ability to ensure that JHA measures reflect its own policies.’ If those are the dangers of not opting in, the dangers of not being a member at all must be even greater.

Third, if we are not participating fully in PCJ measures, this has the capacity to damage our ability to ask for assistance from other countries. Thus the Law Society and Bar Council have noted that even in the current set up ‘not opting into a measure can cause difficulties in cross border co-operation cases where there is an uneven implementation of EU law in the UK, with the result that UK criminal justice authorities may not be in a position to extend the full cooperation sought by another Member State and/or may not receive the full extent of cooperation the UK criminal justice authorities require from other Member States.’

And finally, even if other methods can be found to create similar rues, the EU might be thought to be a particularly efficient method of making these kinds of rules. ‘The EU [argues the Senior European Experts Group] is the right level for co-operation in PCJ because other arrangements, e.g. the Council of Europe, are slower, more costly and less effective than the instruments adopted through the EU. The main reason for that is that there is a properly functioning legal order in the EU which does not exist in the Council of Europe.’

So, in a world where crime is becoming more international, not less, and technology permits greater cooperation between police and criminal justice agencies, courts and so on, we seem to have chosen a path which will reduce our influence over such rules, make it more difficult for us to benefit from them, and at best make the production of such rules in future more inefficient, in a context where we already had as much control and flexibility as we could have wanted.