The socialite was asked by lawyers in the Miami case if she had a diary for business meetings, and she said she simply uses the internet to see where she has been. "I just press my name and Google it and see." Court documents also showed that Hilton earned almost £15 million in 2006 and 2007 from promotions.

The 28-year-old is being sued for $8 million (£5.3 million) by the makers of her 2006 film Pledge This! which failed to perform at the box office. They claim she failed to promote the picture adequately. The hotel heiress and her company, Paris Hilton Entertainment Inc., contend she honoured her deal to promote the film, arguing that the investors made unreasonable and last-minute demands for publicity events when her schedule was already fully booked.

"She's the single busiest person on the planet," Hilton's lawyer Michael Weinstein said during the pre-trial hearing. When she was asked about her responsibilities as an executive producer of the film, she replied: "I'm not sure what a producer does, but - I don't know, help get cool people in the cast." Confronted about her mobile phone usage and calls from the producers, she testified: "With my phone I never know, because I lose it all the time. "I've never seen a phone bill of mine in my life."