All this week, the Daily Mirror has been running a series on Tory finances, including the revelation that the shadow cabinet stands to make £7.1m from David Cameron's plan to cut inheritance tax.

On Wednesday the Tory leader was doorstepped by a Mirror reporter seeking a response. Cameron's comment: "I have no idea what's in the Mirror, but maybe you should try writing for an independent newspaper."

One knows what he means; on occasion I have referred to the Mirror as "the Labour Pravda". But what alternative paper would Cameron suggest for a tabloid hack? Perhaps the non-partisan Sun? Or the fair-minded Daily Mail?

Cameron hasn't previously suggested that papers should remain politically neutral. On the contrary, the morning the Tories were endorsed by the Sun, he told the BBC:

I want to have the widest possible, broadest possible coalition for change, so obviously I welcome any newspaper or business or media organisation that comes on and says the Conservatives have got the right ideas.

You can't call for papers to come out in favour of the Conservative Party and then attack those that don't for lacking political independence.

It was similarly foolish of New Labour apparatchiks to denounce the Sun as a "Tory fanzine" after they had welcomed the red-top's support for years.

Both parties should be far more willing than they are to defend the press's freedom to take political stances. That UK papers are partisan and opinionated is one of the reasons they have fared better than their staid US counterparts. Politicians should recognise the value of this, even when it works against them.

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