One of the problems with most democracies is that they are run by politicians. Politicians are, for the most part, vile, lying, cheating scumbags. It's hard to understand why people keep voting for them. The only convincing explanation I have ever heard is the "wrong lizard" theory, explained by Douglas Adams.

I heard an depressingly splendid example of one of the things that is wrong with politicians on Radio 4's Today programme this morning. Menzies Campbell, a senior member of the Liberal Democrats, was being interviewed in response to a report by the liberal think tank Centre Forum which suggested we should scrap the Trident nuclear deterrent immediately. Campbell was there to put forward the government view, which is that we shouldn't.

Fair enough, you might think. Why shouldn't the government argue that we should keep a nuclear deterrent?

Well, the problem is this. Although Campbell was supposedly responding to the report, he admitted (about 4 min 30 sec into the recording) that he hadn't read it.

Excuse me?

How can he possibly respond to a report that he hasn't read?

This is one of the problems with politicians. They decide on policy first, and then try to find evidence to justify it.

A rational policy maker would consider all the evidence, and then come up with a policy. In contrast, most politicians decide on a policy first, perhaps because they think it will get them votes or perhaps because it helps the financial interests of their mates. Then they look for evidence to support the policy, and ignore any evidence that suggests the policy might be a bad idea.

In Campbell's response to Centre Forum's report, he demonstrates all that's wrong with politicians. He argues that the report was wrong simply on the basis that its conclusions disagreed with government policy. To reach that decision without reading the report is the height of arrogance.

Now, I don't know how much merit there is in the suggestions in Centre Forum's report, because I haven't read it either. But what I do know is that to say its suggestions are not valid without having read it is outrageous. It's disappointing that the normally excellent Evan Davies didn't pick up Campbell on the fact he hadn't read the report. Perhaps that shows just how absolutely routine it has become that politicians take such a dishonest approach to their arguments, and that Evan Davies didn't even regard it as remarkable.

Seriously, why do we put up with this kind of thing from our politicians?