Proposals unveiled at the Conservative party conference this week - dubbed "bash a burglar" - would mean that homeowners who repel intruders would be protected from prosecution unless they used grossly disproportionate force.
But despite this, the Government is still refusing to allow back into the country a high-profile American martial arts instructor on the grounds that his presence "would not be conducive to the public good".
Tim Larkin has been visiting the country for 20 years but was refused entry in the wake of last summer's riots in case he "inflamed community tensions". A UK Border Agency official flew to Las Vegas to hand him a letter just before he was due to board a flight.
Mr Larkin, who has trained US Navy SEALs and US Army Special Forces troops, is now applying for a judicial review of the Home Secretary's decision to bar him from Britain.
And he will further embarrass Theresa May next week when he uses new technology to speak to MPs in the House of Commons via a video link.
His spokesman, Richard Hillgrove, said: "On the one hand the Government is saying it's alright to use a gun or knife to defend your property from intruders.
"So how can an upstanding US citizen, without so much as a parking fine, who teaches safe, sensible, weaponless self defence and who has been coming to Britain for 20 years - be suddenly banned from entering the UK because he is deemed to 'not be conducive to the public good'?
"It makes absolutely no sense whatsoever."
Mr Larkin, a former intelligence officer for the US Navy, has secured the leading law firm Tuckers to challenge the ban on him entering Britain in the High Court.
He says the decision to exclude him was "unfair, unreasonable and disproportionate", as the Home Office never looked into allegations that he was a vigilante who would stir up trouble.
The Home Office claims he was too late to challenge the decision, but Mr Larkin has insisted that he never received the original banning letter dating back to last November, and only found out about it in May.
Legal papers submitted by the Home Office state that the fact that Mr Larkin teaches "fatal techniques" is "sufficient to render his exclusion conducive to the public good".
"There are communities where it would be especially contrary to the public good to permit dissemination of [his] self-proclaimed 'kill or be killed approach' and to train people how to kill."
