Sir Ian Kennedy said the Independent Parliamentary Standards Authority is doing the job intended for it when members of Parliament voted it into existence, The Daily Telegraph reported. He told the BBC the group is there for "the long haul."
''Some MPs find it difficult to come to terms with the notion of independent regulation -- that's the process of getting used to a new world,'' he said.
Roger Gale, a Conservative MP, Bob Russell, a Liberal Democrat and David Winnick from Labor, all had harsh words for the body and its chairman. Gale told the BBC IPSA "does not work and those responsible have got to be replaced."
Prime Minister David Cameron recently called IPSA "anti-family" because of a new rule that MPs cannot claim expenses for moving their children between London and their constituencies.
Kennedy acknowledged IPSA has made mistakes and said the group is trying to address concerns of both MPs and the public. He pointed out that it is taxpayers footing the bill for parliamentary expenses.
Notable deaths of 2014 [PHOTOS]
U.N. investigator: prosecute North Korea