The Prime Minister must make sure that any reduction in involvement with Europe wide crime-fighting bodies does not decrease Britain's ability to bring criminals to justice. Our Prime Minister needs to ensure that our departure from Europol (the European Union Agency for Law Enforcement Cooperation), Eurojust (the European judicial cooperation agency) and the European Anti-Fraud Office at the end of this year does not reduce in any way the amount of information passed between those agencies and the UK and the speeds at which those processes occur. What's more he needs to ensure that European Arrest Warrants (or an exact equivalent) can still be used to bring criminals to justice in the same way that they were used before Brexit.

Brexit-related promises (about fighting crime) from Boris Johnson and his colleagues:

Perhaps significantly, there were virtually none. Despite the problems posed by conventional international crime, there was zero mention of it in the Vote Leave campaign manifesto, drawn up by that organisation's campaign committee of which Boris Johnson was a prominent member.