Do you think that MP's should repay the money they swindled out of the taxpayer?

Morally I believe they should repay the tax payers' money they have received but legally I suspect they may be quite correct in their belief that they claimed the expenses based upon the rules that were in place at that time. However, I suspect their electorate will judge their actions to be immoral and they will not be chosen to stand at the election in 2010.