Michael Phelps leaving a restaurant on January 4, 2009 in Miami Beach, Florida.Us MagazineSee the Michael Phelps drug photos.
"I engaged in behavior which was regrettable and demonstrated bad judgment," Phelps said in a statement released to the Associated Press, and posted on his Facebook page, Sunday. "I'm 23 years old and despite the successes I've had in the pool, I acted in a youthful and inappropriate way, not in a manner people have come to expect from me. For this, I am sorry. I promise my fans and the public it will not happen again."
The photos were snapped in November -- three months after he set records by winning eight gold medals at the Beijing Olympics -- at a University of South Carolina house party.
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Marijuana is banned under World Anti-Doping Agency rules. Athletes caught using drugs could face a two-year ban from the Olympics. Also at stake: his endorsement deals, which ABC estimated could be worth $100 million over the course of his lifetime.
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The U.S. Olympic Committee released a statement saying it was "disappointed in the behavior recently exhibited by Michael Phelps ."
"Michael has acknowledged that he made a mistake and apologized for his actions," the statement continued. "We are confident that, going forward, Michael will consistently set the type of example we all expect from a great Olympic champion."
This isn't the first time Phelps has faced controversy. In 2004 -- the same year he won six gold and two bronze medals in Athens -- he was sentenced to 18 months probation for drunk driving.
