The government plans to exercise its right to opt out of 130 European Union measures on law and order, Home Secretary Theresa May says.
This takes up an option that was agreed by the last government in the negotiations leading up to the Lisbon Treaty in 2010.
For Eurosceptics, it is seen as an overdue repatriation of powers but for others it is a plan that will weaken cooperation in areas including extradition.
Two former home secretaries – Charles Clarke and Michael Howard – disagree on whether opting out would be a sensible move for the UK.
Speaking to the Today programme, former Conservative party leader Lord Howard said: “What we’ll gain is the ability to make our own judgements about which of these measures we want to opt back into.
“It’s perfectly possible to cooperate with our European partners in many different ways.”
But Charles Clarke, home secretary under Tony Blair, believes that opting out of the measures would be a bad decision.
“I think it’s a pretty wrong development,” he said.
“The home secretary’s own threat assessment stated that the threats come from drug trafficking, organised immigration crime, frauds and terrorism. It also said the things you need to contest those crimes are strong intelligence and strong international cooperation.
“The idea that we can just do it within the UK is complete nonsense. There’s a whole stream of databases which these treaties will mean that we can no longer use to track down criminals. We have the police cooperation, the judicial cooperation… it’s just madness to pull out of all these things.”
This audio has been editied from the broadcast version.