Facing growing questions after Usman Khan killed two people before being shot dead by police – after being released on licence less than a year ago – the prime minister beefed up his plans for longer sentences.
He also risked fresh controversy by blaming the Brexit logjam for the failure to act sooner, claiming: “Due to the broken hung parliament that was preoccupied with blocking Brexit, we could not do more.”
Mr Johnson blamed “laws passed in 2008 which established automatic early release” for Khan’s release, when Gordon Brown was the Labour prime minister.
And he said: “This system has got to end – I repeat, this has got to end, as I‘ve been saying for four months.
“If you are convicted of a serious terrorist offence, there should be a mandatory minimum sentence of 14 years – and some should never be released.
“Further, for all terrorism and extremist offences, the sentence announced by the judge must be the time actually served – these criminals must serve every day of their sentence, with no exceptions.”
Mr Johnson claimed: “These simple changes, in line with what I’ve been saying since becoming prime minister, would have prevented this attack.”
And he said: “What I have seen over the last 24 hours has made me angry – it’s absolutely clear that we can’t carry on with the failed approaches of the past.”
The fightback came after a former top prosecutor revealed he personally warned Mr Johnson about the risk posed by freeing terrorists who had not been deradicalised, but was told there was “no money”.
The hugely damaging claim came as the solicitor for the London Bridge attacker said he had asked for help to turn away from terrorism while in prison, but was not given any.
Jeremy Corbyn branded the attack he was able to carry out “a complete disaster”, saying: “There has got to be a very full investigation.”
The focus switched to efforts made to deradicalise prisoners when Nazir Afzal, the former chief prosecutor for northwest England, intervened by revealing his private conversation with Mr Johnson.
He said he had raised the problem of terrorists being released “whilst ostensibly rehabilitated but still radicalised” in many government meetings, before raising it with Mr Johnson in June 2016.
“He asked me what keeps me awake at night and I told him it was this issue,” Mr Afzal said.
“When he wanted to know what to do about it, I told him it was more resources for one-to-one deradicalisation.
“Back then, he hadn’t found the ‘money tree’ so he frustratingly said there was no money.”
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