Liberal Democrats have sharply criticised their own government ministers for failing to stop the so-called bedroom tax.
Party members, gathered at the spring conference in Dundee, called on the coalition Government to defer the under-occupancy rules and reconsider its approach. Just one Lib Dem openly backed the Government policy at the end of a debate on the emergency motion.
Former Lib Dem MSP Robert Brown, now a councillor, led the criticism, saying the change will mean a cut to people's "survival income". He said: "I hope that conference will send the clearest of messages to the Government, to Liberal Democrat ministers, that the policy is damaging and unfair."
Another former MSP, Mike Rumbles, said he appreciates the party must make compromises in government. "But taking an average £8 a week to encourage people to move to a smaller home is a nonsense," he said. The policy is mean spirited, he told delegates.
The move follows the party's rejection of plans for "secret courts" in the Justice and Security Bill. That decision was made on the day Deputy Prime Minister Nick Clegg made his keynote speech to conference.
Speaking during a question and answers session on business issues at the conference on Friday, Scottish Lib Dem leader Willie Rennie said: "The bedroom tax is tough, but it is central to the welfare reforms. If we believe in the principle of making work pay, we need to reform the welfare system to be able to cover that. Now, if you've got a house that you couldn't afford if you were working, that traps you on welfare, and I think we should incentivise people out of welfare."
Mr Rennie said his party was working with housing associations to make sure people do not suffer unintended consequences, and was "sensitive" to concerns about the bedroom tax.
Labour MP Margaret Curran, the shadow Scottish secretary, said Lib Dems are helping to carry unpopular Tory policies.
"Not a single delegate spoke in favour of the bedroom tax at the Scottish Liberal Democrat conference, but the Scottish Lib Dems around the cabinet table - Michael Moore and Danny Alexander - want to support the Tories and carry on with a policy that will punish some of the most vulnerable people in our communities," she said in a statement issued by the party.
"100,000 tenants in Scotland will be hit by the bedroom tax, 40,000 face rent arrears and thousands could be made homeless. The bedroom tax is cruel and unfair and today's vote shows even the Lib Dems know that. Michael Moore and Danny Alexander should listen to people across Scotland, and their own members, who want this policy reversed and do the right thing in this week's Budget."