Former Labour MP Margaret Moran fiddled her expenses claims to receive more than £53,000, a jury ruled today.
The 57-year-old claimed nearly her entire annual allowance in one bogus expense entry and forged invoices for more than £20,000 of non-existent goods and services.
Moran, who served as MP for Luton South from 1997 until the 2010 General Election, was found to have falsely claimed around £60,000 in parliamentary expenses between 2004 and 2008, of which she received £53,000.
However, jurors at Southwark Crown Court in London were unable to return a guilty verdict after it was ruled that Moran was unfit to stand trial for mental health reasons.
Instead, the jury found that she had committed 15 counts of false accounting.
The court had heard that she was able to make a dry rot claim of £22,500 by "flipping" her two homes - changing which property was her second home and therefore allowing her to claim expenses on it.
Moran's false expenses claims are the largest amount uncovered in the wake of the MPs' expenses scandal, brought to light by the Daily Telegraph in 2009.
Mr Justice Saunders is expected to sentence Moran at a future hearing.
She may be subject to a supervision order, a hospital order or absolute discharge, where no further action is taken against her.