The government is to exercise its opt-out of 135 European crime and justice measures pre-dating the 2007 Lisbon Treaty – but hopes to rejoin some 30, including the European arrest warrant and the law enforcement agency Europol, the home secretary said today.

In a well-trailed statement to the House of Commons, Theresa May (pictured) promised to hold parliamentary debates on the opt-out decision as well as on which measures and institutions the UK would seek to rejoin. She said the government would use UK law to amend the use of the European arrest warrant for minor crimes.

Under a provision negotiated by the Labour government, the UK has until 31 May next year to decide whether to withdraw from all European Union police and criminal justice measures that pre-dated the Lisbon treaty. Remaining in would place the relevant competences under the jurisdiction of Court of Justice of the European Union, a step strongly opposed in the Conservative Party.

May told parliament that her decision was based on ‘principle, policy and pragmatism’. The opt out comes in to effect from 1 December 2014 and negotiations with the European Commission and other member states on rejoining specific measures would begin immediately, she said.

While stressing the importance of the European arrest warrant as ‘a valuable tool in returning offenders to face justice’, May promised to introduce new safeguards under UK law. These include:

  • An amendment to the Anti-Social Behaviour, Crime and Policing Bill, currently in committee stage, ‘to ensure that an arrest warrant can be refused for minor crimes’.
  • An amendment to the Extradition Act to ensure that people in the UK can be extradited only when the requesting state has already made a decision to charge and a decision to try, to reduce the risk of lengthy pre-trial detention.
  • Enabling judges to refuse extradition if part of the offence was committed in the UK and was not illegal in the UK.

May also said that the UK would apply to rejoin Europol – but not if its powers were extended to direct national governments.

‘We believe in operational independence for our police forces in the UK and are not prepared to see Europol mandate police forces in the UK,’ she said.

Speaking for the opposition, shadow home secretary Yvette Cooper said that the home secretary had been forced to admit that the UK needs the European arrest warrant. Criticising the short timetable for a debate, Cooper said: ‘This is the wrong strategy and the wrong way to make policy on crime and justice.’

Jago Russell, chief executive of pressure group Fair Trials International, said: 'It makes complete sense for the UK to work with the rest of Europe to fight serious crime, but countless cases of injustice have shown that the arrest warrant needs to be reformed. The government must now follow-up on its promise to fix the flaws with Europe’s fast-track extradition regime, to stop it being used for minor crimes and to prevent people being shipped off to foreign prisons to be detained for years before their trial.'