The Government is celebrating the decision by MPs to reject a Lords amendment to the EU Referendum Bill which would have extended the franchise to 16- and 17-year-olds. Labour and Lib Dem peers proposed the change specifically to disrupt the Conservative manifesto promise to hold a referendum, and to try to skew the outcome of that vote when it eventually takes place. Both are scurrilous reasons to change the constitution – monkeying with the way the nation runs for short-term political advantage.

However, the Government itself ought to be wary of the same short-termist approach to the constitution. The Commons clerks have decided that, because a change in the franchise would cost £6 million, the issue is covered by financial privilege, and therefore the Commons can overrule the Lords on the matter.

This may well prove a very effective tactic – presuming peers accept the ruling and don’t push the matter further – but it is also an even bigger piece of constitutional jiggery-pokery than the original amendment. (It should be noted that the Government denies any involvement in the decision, though it is rather convenient and has surprised experienced parliamentarians in both Houses.)

If the measure of financial privilege is to be whether a Bill costs the taxpayer any money at all, then every single proposal the Commons considers would fit the definition of a Money Bill. Effectively, this would be a vast extension of the scope of the Parliament Act, and an equally vast diminution of the powers of the Lords, without a minute’s debate, still less a change in the law.

This is no way to run a country. By all means there should be a debate on the composition, role and powers of the Lords – personally, I would lean towards a directly-elected chamber of some sort, while the ConHome manifesto recommended changing the means of appointment and giving some seats to directly-elected mayors – but that debate requires parliamentary time, wide consultation and national discussion about how our Parliament ought to work. Changing the system on the fly in order to win a skirmish over the voting age will produce neither a sustainable solution nor widespread agreement – and it doesn’t take a psychic to see how a future Labour government could exploit this change to force through bad ideas of which we would all disapprove.

We are meant to be better than this. Conservatives ought to respect the heritage of our institutions, and change them only for good reasons – messing with the basic rules of Parliament for mere political gain runs contrary to all of the fundamental principles of our movement. The Government may be ringing the bells now, but this short-termism may give us all cause to wring our hands before too long.