The Green party have begun their by-election campaign against David Davis in Haltemprice and Howden.
Paradoxically, the party are standing against him on a civil liberties platform, with claims Mr Davis is too authoritarian.
Shan Oakes, the Green candidate, will be joined on the campaign trail by veteran gay and human rights activist Peter Thatchell.
Green Party principal speaker Derek Wall said: "This by-election was supposed to be about civil liberties. But it's been called by a man - David Davis - who thinks it's okay for the government to lock you up for four weeks without even telling you what you're supposed to have done.
"David Davis also believes that you should have no right to criticise the government within a mile of parliament."
"So the Green Party had to stand. Someone had to stand up for civil liberties."
The emergence of a Green candidate makes an already unique by-election even more strange. Despite being unable to find someone to stand against him on an authoritarian or anti-terror platform, Mr Davis seems to have found someone attacking him from the other direction.