By Nick Assinder
Political Correspondent, BBC News Website
After all the talk of openness and transparency in Parliament, it may have come as a surprise to many that MPs have only now been forced to reveal details of the amounts they claim from taxpayers in travel expenses.
Many MPs claim thousands in car hire and taxi fees
Indeed, it has only come after a two year Freedom of Information battle between Liberal Democrat Norman Baker and the Commons authorities, who claimed the move would breach data protection rules.
It follows the decision in 2004 to published the overall cost of MPs allowances and expenses, without all the details.
Apart from the Commons authorities' opposition, there were plenty of MPs who also opposed the move, partly on the grounds it could lead to pressure on them to cut necessary costs and, as a result, undermine their constituency work.
Former Tory whip David Maclean is currently attempting to bring in a new law which would exempt MPs and Peers from the Freedom of Information laws. Backbench bills rarely become law but this one has thus far sailed through all its stages and has now been given parliamentary time by Commons leader Jack Straw.
Others, however, argue that taxpayers have a right to know where their money goes and that it is up to the individuals to justify their spending.
Unlike other national parliaments, such as the Scottish Parliament, there has been a history of privacy - some would say secrecy - surrounding the way politicians spend taxpayers' money.
When the register of members' interests was first introduced 30 years ago, there was much anger at the fact that MPs were expected to set out where they derived their other incomes from.
There was at least one senior MP who simply refused to comply on the grounds it was nobody else's business, while others only listed things they believed had a direct bearing on their work in the Commons.
It has been claimed, although it is impossible to prove, that this bit of openness had a direct effect on the sort of external work some MPs have since undertaken - that they are extremely cautious about the sort of organisations or businesses they take money from.
It has, on the other hand, also led to an annual "contest" to see who has earned the most from making after-dinner speeches and the like, with former Tory leader William Hague recently topping that particular popularity poll.
It is now being suggested the fact that MPs have been required to detail their travelling expenses may lead to a reduction in those costs, and that it might see fewer apparent anomalies between MPs' claims.
'Ought to know'
It is also being claimed by Mr Baker that it should help the environment by persuading more to abandon their cars or planes in favour of trains and cycles, and to consider whether their journeys are really necessary in the first place.
"If MPs are saying that climate change is very important, yet are continually taking the plane, that's a matter their constituents ought to know about," he said.
However, it is also argued that one of the most important duties undertaken by any MP is to represent his or her constituents.
And they soon come under fire if they are believed to be spending too little time among the people who elected them.
It has to be said, though, that many MPs have come to the view that this sort of transparency is now inevitable, whether they like it or not because it is the most effective way of countering any public view of politicians as having their "snouts in the trough".
That may be seen as a sad reflection on the current relationship between voters and MPs, but the days when the argument "we are all honourable members" would defeat such attitudes appear long gone.