Twitter may be Paris Hilton’s undoing. Last weekend, in Las Vegas, the Hollywood socialite was arrested and the police found a small bag of cocaine in her Chanel purse. Paris defended, saying she borrowed the purse from a friend. But now, a picture posted on Twitter by her a month ago may have nailed her lie. The photograph shows a Chanel purse very similar to the one Paris had in Las Vegas. “Love My New Chanel Purse I got Today,” she had posted.