The public has a right to be angry – very angry – about the various ways that many MPs have fiddled expenses. And we are all heartily sick of the standard excuse: “I have done nothing wrong”.

In fact, MPs have been helping themselves from public funds in various ways which have included fraud, lying and bending the rules, but they do not constitute the much more serious charge of corruption. 

Corruption occurs when a corruptor covertly gives a favour to a corruptee to influence actions that benefit the corruptor for which the corruptee has authority.

It is vital to distinguish corruption from theft and fraud otherwise the term “corrupt” becomes so poorly defined as to be valueless. MPs who claimed allowances for non-existent mortgage repayments were guilty of fraud but not of corruption. However, in the case of two peers who were recently accused of offering to influence legislation in exchange for covert fees, this clearly was or would have been corrupt under my definition if the actions had taken place.

In conclusion, the Commons’ expenses system has been exposed as an Augean stable which an overwhelming majority of MPs wanted to hush up. It needs cleaning out because it was lax and misused. But it wasn’t corrupt as such.

People who find this a surprising conclusion may wish to read the detailed arguments and explanations in my monograph.

Ian Senior is the author of Corruption – The World’s Big C.