Hotel heiress Paris Hilton has admitted something the rest of the world already knew - she's not that bright. The 25-year-old star of The Simple Life made her confession to cops quizzing her about a burglary at the home of Girls Gone Wild creator Joe Francis.

She was hailed as a crime-fighter when she told Francis, who has made a fortune selling raunchy videos of topless college girls partying, she had overheard on the party scene that a Hollywood hanger-on called Darnell Riley had boasted of breaking into his house.

But when she was quizzed by Los Angeles police it emerged she wasn't a reliable witness as she could not remember what happened. "Like I really, I don't remember," she said on police tapes obtained by the television show Dateline. "I'm not, like, that smart. I forget stuff all the time."

Riley was arrested after Hilton's tip-off, and earlier this year was sentenced to nearly 11 years in prison after pleading guilty to residential burglary and attempted extortion.

During the raid he took video showing Francis tied up with his trousers pulled down, while Riley taunted him with a sex toy.

Hilton also told police she was the victim of extortion, after 'private tapes' were stolen from her home and an anonymous caller offered to sell them back to her, but that she followed her father's advice and refused to pay up.

"They wanted money," she said. "They were tryin' to sell it to like a newspaper or something. So if you pay somebody, then you're gonna be paying for the rest of your life. My dad always taught me. They'll keep the tape anyway." Dateline also obtained video of Francis being humiliated but has no plans to show it.