"Laughable" counter-terrorism plans by desperate Tory leadership contender Rishi Sunak could end up targeting "thought crimes", experts warn.
The former Chancellor announced he plans to shake-up definitions of extremism if he becomes PM - targeting "vilification of the United Kingdom".
But it has sparked warnings this would likely be impossible to enact, could benefit far-right fanatics and may be used to target dissent.
Mr Sunak said he wants the counter-terrorist Prevent programme to focus on Islamic extremism in an effort to appeal to the Tory party members who will decide who enters No 10 next month.
The wannabe PM - who has a huge uphill battle on his hands if he's going to overtake favourite Liz Truss - said: "Whether redoubling our efforts to tackle Islamist extremism or rooting out those who are vocal in their hatred of our country, I will do whatever it takes to fulfil that duty.
"Britain is a beacon of freedom, tolerance and diversity. We must never let those who seek to undermine and destroy our way of life to succeed."
It prompted immediate accusations of "straying into thought crimes".
Former counter-terrorism chief and ex chief constable of Greater Manchester Police Sir Peter Fahy said widening Prevent "could damage its credibility and reputation".
He told The Guardian : "It makes it more about people’s thoughts and opinions. It is straying into thought crimes and political opinions.”
And Sir Peter added: "Political opposition is not where police should be, it is those who pose a serious threat and risk of violence, not those opposed to political systems."
Mr Sunak's team said the definition of vilification would not be legally binding, and said criticism of the government or its policies would not be included.
It said there have been "too many examples" of publicly funded charities and organisations accused of promoting extremist ideology in the UK - without giving examples.
Counter-terrorism expert Dr Maria Norris, honorary fellow at the Politics and International Studies (PAIS) department at The University of Warwick, posted on Twitter : "This is as laughable as it is problematic.
"How will they define extreme hatred of Britain? They can’t, so this will serve to 1) vilify dissent and 2) continue to target minority communities."
Dr Norris continued: "It is very easy for a government invested in the culture wars, to frame any criticism as hatred of Britain. So this is about dissent."
And she warned that Mr Sunak's proposals would let far-right extremists off the hook, stating: "The only example of 'hating the UK' given is attacking the British troops.
"So this is unlikely to be about far-right extremism and neo-nazis who are generally rabid in their support for the army. Prevent is racial by design, and so is this."
Anne McLaughlin MP, the SNP's Shadow Justice spokesperson, said: "These dangerous and ill-thought-out proposals from Rishi Sunak are yet another reminder of the depths to which this toxic Tory leadership race has sunk.
"Rather than pandering to right-wing Tory backbenchers and party members, Rishi Sunak and Liz Truss should be more focused on the fact that people across these islands are facing the most horrendous rise in the cost of living most of us have ever seen and it’s under their watch."
