MPs are being pressed to vote against a controversial amendment to the Freedom of Information Act later this week that will exempt them from having to publish detailed expenses.

The digital democracy charity mySociety.org is leading a letter-writing campaign to stop parliamentarians changing the law to keep their use of public money secret. It has dedicated the front page of its most popular website, TheyWorkForYou.com, to the cause until the vote on Thursday.

Tom Steinberg, head of mySociety, said: "Our explicit goal is to have a lot of constituents from around the country let their MPs know they won't be impressed with a 'yes' vote or an abstention (the same thing in this case), and to build our Facebook group to the point where the mainstream media starts to take notice of this net-driven discontent."

TheyWorkForYou.com grabs data from Hansard and other official parliamentary publications, and allows constituents to easily track how their MPs vote. "After the vote, we'll be prominently publishing who voted which way - there should be a couple of million visitors at least before the next election," Steinberg said.

There are details of how to contact your MP about their expenses here. ®

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