Students of British politics will recall that the speaker of the House of Commons Michael Martin was forced to resign earlier this year because of an expenses scandal. His crime? To resist making public the expenses claims – many of them extravagant – which were submitted by MPs. He even called in the police to investigate the source of a leak about those claims when many people were expecting him to apologise to the British people about the greed of their MPs.

But there were no accusations that Martin himself had spent taxpayers' money too freely. What finished his career was that he did not properly understand how angry people were at the greed of their public representatives. He could therefore not properly respond to that anger.

John O'Donoghue, Martin's equivalent in Dáil éireann, cannot be accused of taking a responsible approach to expenses claims. Stories in this newspaper over the last two weeks, and again today, show him to have spent quite staggering amounts of taxpayers' money on a variety of trips during his last two years as minister for arts, sport and tourism. He also used the government jet as though it were his own private plane, flying from the Cannes film festival to Kerry, and back again, merely to attend to a constituency matter.

In many ways, today's revelations are as serious; the fact he felt it was reasonable to pay €1,400 for a chauffeur and a car to drive him from his hotel to the Cheltenham racecourse on five successive days suggests a minister – and a system – that was out of control. Nothing he did on that occasion or during the many other trips we have reported on was against the law or against the (very lax) rules and regulations which governed expenses. But it was nevertheless a reprehensible misuse of taxpayers' money.

There is no point in calling on O'Donoghue to resign as Ceann Comhairle. Fianna Fáil politicians do not have a strong record of realising when they have behaved badly, still less resigning over it. Would it be too much to ask, however, that O'Donoghue step down immediately as chairman of the Oireachtas Commission, the body recently charged with reforming the expenses system for TDs and senators? O'Donoghue has no credibility in this area.

His continued presence at the head of a body which may well have to deal with the expenses issue again brings the Oireachtas into disrepute at a time when it can afford no further damage to its reputation.