Politics, as the saying goes, is show business for ugly people. So if you want to add a bit of glamour and beauty to your party, what’s wrong with using a picture of Kate Winslet in your promotional material?

Quite a lot, it seems. The Liberal Democrat leader, Nick Clegg, faced embarrassment yesterday after it emerged that his party used a photo of the Oscar-winning actress for an advert in its conference brochure – without obtaining her permission.

A picture of her on the red carpet at the 2007 Golden Globes was doctored to make it look as though she was at the Lib Dem Council Awards at the party’s conference in Harrogate on Friday evening.

The colour picture was used prominently on page two of the spring conference agenda, handed out to thousands of conference delegates, and is free to download from the party’s website. With a reference to Ms Winslet’s gushing speech at this year’s Golden Globes ceremony, the advert read: “Winning can be emotional!”

The blunder is doubly embarrassing for the Lib Dem leader because he is friends with Ms Winslet’s husband, the director Sam Mendes.

The picture left the impression that Ms Winslet, who has never revealed her political affiliations, was a Lib Dem supporter.

A spokeswoman for Ms Winslet said: “They did not request permission to use the image and, so far, Kate has not been made aware of its use. I am not aware of her political position.”

Legal sources said the actress would have a case to sue the Lib Dems for passing off a false endorsement. There have been previous cases where celebrities of global fame have claimed substantial damages after they were used in advertising material.

A Lib Dem spokesman said the party believed it was “allowed to use contemporaneous figures in current affairs adverts” and cited Ryanair using Tony Blair and Gordon Brown in its material. However, politicians tend to ignore infringements because they are part of the normal party political “attack” adverts, while actors have a commercial image to protect.

A spokesman for the Lib Dem local government group behind the advert said: “It was a humorous piece for a fairly low-key event.” Asked whether it showed that Ms Winslet was a Lib Dem supporter, he said: “That is not the idea…. We are more than happy to make it clear that it is not the case.”

Last year Ms Winslet denied claims that pictures of her in Vanity Fair were airbrushed, while in 2003 GQ apologised for digitally altering photos to make her look slimmer.

SOURCE:  The Independent on Sunday