Three British Labour MPs and a Conservative peer are facing criminal charges over their expense claims.
All four parliamentarians deny the allegations and pledged to stage a robust defence after the Director of Public Prosecutions Keir Starmer announced the legal action.
They will appear before Westminster Crown Court on March 11.
Elliot Morley has been charged on two counts of false accounting under the 1958 Theft Act over alleged excessive mortgage claims.
David Chaytor has been charged with three counts of false accounting; relating to rent claims on a house he owned and claims for a house owned by his mother.
Jim Devine is accused of using false invoices to dishonestly claim thousands of pounds for cleaning services and stationery. While Lord Hanningfield is alleged to have illegally claimed overnight expenses.
The charges have arisen after an investigation by former civil servant Sir Thomas Legg. He was tasked with unearthing the details of an alleged corruption scandal that has rocked the Houses of Parliament to their foundations with claims for bizarre items such as a duck house.
Prime Minister Gordon Brown has publicly stated his anger over what he called very serious criminal allegations which have done much to undermine public confidence in government.