By Paul Goodman
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The House of Commons has transformed itself over the past 25 years, with increasing speed, from a chamber of citizen legislators, who were funded by private interests, to one of professional politicians, who are financed by the taxpayer.
I believe this is a change for the worse, and the complaint that "they're all the same" – that we're governed by an identikit political class – has much to do with the decline of the Conservative Party and the rise of UKIP, not to mention the fall in voter turnout.
The quality of MPs, however, is unchanged, broadly speaking. Nicola Blackwood, Zac Goldsmith, Andrea Leadsom, Charlotte Leslie, Jesse Norman, Rory Stewart…like them or loathe them, the backbenches contain as much talent as ever.
A beneficial side-effect of the professionalisation of politics is that voters see MPs as their employees, and thus want them to be consistuency champions, standing up to the Whips. But be that as it may, I didn't believe, when I left the Commons, that the standard of MPs would decline.
However, I predicted that though the quality would stay much the same, the turnover would rise. The new breed of MPs would no longer work his way up the political ladder, become a Minister, and after leaving office stay in the House while pursuing outside interests.
Instead, thwarted by the restrictions on the pursuit of such interests, he would leave. "The best of the next generation will get in quick, struggle to the top – and, once there, get out quicker to make money," I wrote.
David Miliband has not exactly gone to make money, but his departure from the Commons (which Peter Hoskin reported yesterday) is, like that of James Purnell, a sign of the times. He has gone because he didn't become Labour leader – and because he didn't expect to be its leader in the future.
It goes almost without saying that the psychodrama of his struggle with his brother also lies behind his going. But his decision to leave says something about the Commons as well as about David Miliband. It's a place that people want to stay in for less long.
That will have a knock-on effect of its usefulness. The Chamber will start to run short of the kind of ex-Minister who can say: "We tried that – and it didn't work." (Or, better: "But if we'd have tried this it might have done."
In the other words, the Commons will have plenty of bright young things, but be short on the voice of experience. And while experience can be over-sold, it's a vital commodity in an elected chamber. The Commons is becoming a diminished place.