The "slow death" of civil liberties must be reversed, the Liberal Democrats said today as the party pledged to scrap 20 laws that it said infringed people's freedom.

In a move designed to ratchet up the pressure on the government, Chris Huhne, the party's home affairs spokesman, published a freedom bill that aims to reverse the "cumulative loss" of civil liberties in Britain.

The draft legislation brings together all the laws introduced by Conservative and Labour governments over the last two decades that the party believes should be repealed.

Huhne said the party planned to introduce some of the measures as amendments to the bill of rights and responsibilities that the government is expected to bring forward.

Measures in the Lib Dem bill include abolishing the veto on the Freedom of Information Act, used for the first time this week by Jack Straw, the justice minister, to block publication of the minutes of two cabinet meetings held in the run-up to the Iraq war.

The wishlist also includes halving the period of detention without charge from 28 to 14 days, scrapping the ID card scheme, removing all innocent people from the DNA database other than those tried for a violent or sexual offences, and restricting the Regulation of Investigatory Powers Act to serious and terrorist offences to stop councils and other public bodies "snooping" on citizens.

Huhne said: "With one small change after another over the last 20 years, the cumulative loss of civil liberties is huge. The government has presided over the slow death by a thousand cuts of our hard-won British freedoms.

"Our forebears who fought so hard to establish our rights under the law would be shocked at what we have lost. The freedom bill we are publishing today will repeal 20 years of attacks on our civil liberties from both Labour and Tory governments."

Huhne expressed concern about the government's forthcoming bill of rights and responsibilities.

"It probably won't add any new rights and will probably add new responsibilities. A lot of the mood music around a British bill of rights and responsibilities is that we would define rights for British citizens and not anyone else."

David Howarth, the Lib Dems' justice spokesman, estimated there was a group of about 90 politicians from across the political spectrum who always voted in a liberal manner but Huhne said he would expect wider support on the scale last seen when Labour backbenchers rebelled against the government on plans to increase the period of detention without charge from 28 to 42 days.

Though the government was not defeated, 315 MPs voted for it, while 306 voted against – including 36 Labour MPs.

But Huhne said he was unsure that the Tory support for liberal measures they had enjoyed when David Davis was shadow home secretary would continue under Chris Grayling, his successor. The home affairs spokesman said the Tories were now "less friendly to civil liberties".

The idea of a freedom bill was first suggested by the Lib Dem leader, Nick Clegg, in 2006, when he was the party's home affairs spokesman.

The party has launched a website alongside the bill to garner views and allow members of the public to suggest other measures that should be included.