The House of Lords is up for reform. By the time you read this article, the Commons will have voted on whether and how it ought to change.

As constitutional oddities go, the House of Lords is one of the most eccentric places in the world. If you were trying to invent a second chamber, no-one would propose a mixture of bishops, hereditary peers and Tony's cronies as a shining example of a modern and effective Parliament. It owes more to Gilbert and Sullivan than good government.

But, oddly, it seems to work. It’s the Parliamentary equivalent of a bumblebee. In theory it shouldn’t be able to fly, but somehow it manages fine.

So the problem isn’t that the Lords are an odd mixture of people. It’s that they haven’t got enough power to face down the Commons when we get things wrong. The whole point of a second chamber is to tell the Commons to think again, and to improve the quality of our laws. To do that, they need the credibility of a democratic mandate. To be electorally legitimate in modern Britain, they need to be elected. Anything less and, in a tussle with the Commons, they’d be guaranteed to lose.

There's plenty of scope for debate about the type of elections, of course. Academics and experts will argue for hours about whether, for example, proportional systems are better than electoral colleges. I think the most important point is that an elected Lords shouldn’t just duplicate the Commons. We’ve already got too many MPs and we certainly don’t need any more. I’d like us to choose a system of elections which is less party-political and gives high-calibre independent elected experts a chance to shine. Then we’d have a second chamber to be proud of.