Who benefited from the secrecy of MPs' expenses? In 2007 members of the House of Commons Commission and their allies attempted to get the Freedom of Information Act amended to prevent the disclosure of this information. One might speculate that such people had something to gain from doing so.

Commons expenses are managed by a body called the Fees Office, which is effectively subordinate to this Commission. It has now been revealed that the Office, and senior MPs, literally encouraged some MPs to maximise their use of the allowances and expenses system. This money was characterised as being money that the MPs ought to receive but could not as the public was opposed to greater direct salaries. As such, its receipt was conditional on MPs' behaviour. MPs thus compromised would be less likely to oppose those who ran and knew about the expenses system.

It has been known for centuries that financial dependency assorts ill with decision-making independence. This is the justification for paying MPs (and judges) such high salaries in the first place. This is why the practice of having too much of the legislature on the Crown's payroll was banned in the Act of Settlement 1701, and we still regulate the number of ministers. Indeed the very mechanism for resigning from the Commons consists in applying for a Crown office reserved for that purpose. The expenses system thus achieves an effect known to be constitutionally improper and illegal if achieved by more straightforward means. Fewer actual taxpaying constituents' votes and views matter when the behaviour of their MPs can be influenced in this way.

So who is the House of Commons Commission? It is, roughly speaking, the whips of the major parties and the Speaker, whose election in turn used to depend on the whips (though no longer).

Publishing the expense information reduces the power of the whips over the backbenchers, in favour of the power of their constituents, and this is a good thing.

The usual malcontents are trying to use the current crisis as an excuse to push for their favourite constitutional "reform" schemes such as an elected Upper House, electoral "reform", fixed-term parliaments and other cryptorepublican schemes, rather than measures targeted at the actual abuses taking place at present. The only one of these off-topic proposals for change which attracts my sympathy is primary elections for the House of Commons.

Primary elections were previously problematic in the UK because its liberal (in the sense of non-corporatist) constitution succeeded in failing to recognise political parties as such. Following an election whose outcome was influenced by a candidate whose party affiliation was contrived to mislead, we now have state recognition of political parties. We do not, however, have fixed-term parliaments, and thus is it not obvious when to hold a primary election.

Now we could adopt fixed-term parliaments, but that no longer has much to do with redressing the balance between taxpayers and party whips. It involves changing the conditions under which Parliament may be dissolved. These are currently not under the control of politicians, but that would have to change to move to fixed-term parliaments, as the choice currently rests with the Head of State and is exercised according to the Lascelles Principles. The most recent occasion on which this made a difference was after the resignation of Tony Blair as leader of Labour. Had he called a general election once it looked like Brown would win the party leadership, the Queen would not have granted one. The subtleties involved here would have to be enacted in statute, and thus become subject to the whims of future parliamentary majorities, and one might ask again ... who benefits?

As a compromise, primary elections could be held three years after the most recent general election, and constitute a mandate for the next five years (being the maximum life of the House of Commons). This would reduce the power of party hierarchies to threaten MPs with deselection, and independence of MPs is paramount.