Located at rank.libdemvoice.org, the digital tool rates MPs according to their voting records on 10 key issues, including such hot-button liberal topics as ID cards, control orders and trials without jury.
MPs are then marked out of 100 in terms of how authoritarian they are. ‘Although politics is often talked about in terms of left vs right, for a lot of people the liberal/authoritarian spectrum is the more important one,' LibDemVoice editor Mark Pack told PRWeek.
‘It's one that tends to get a bit more overlooked but is often what distinguishes people.'
The site will be launched this evening as the Liberal Democrats spring conference gets under way.
Pack said that the political parties themselves would be uncomfortable with this type of initiative. ‘This is not an official party thing. Overall Lib Dem MPs come out pretty well but there are individual MPs in other parties who come out well.'