Actor Shia LaBeouf bitterly regrets his 2007 arrest for trespassing in a Chicago, Illinois drugstore, insisting the incident occurred in a moment of "utter insanity." The Transformers star, 21, was charged with a public misdemeanor in November, after refusing to leave the store while drunk. The charges were later dropped. But LaBeouf admits the bizarre event was an isolated incident, which he is putting behind him as a life lesson. He tells British magazine Empire, "That was complete and utter insanity. I was an a*****e, and it was a mistake I'm still completely embarrassed about. I was in the middle of a strange mind state, having just come off a three-month window of focus. I can't diminish what happened at all. But I can say this: I'm not the first 21-year-old to be arrested for a misdemeanor. There are lessons in life I need to learn, and I'm learning all of them in front of the public."