The Tv personality, who is a member of People for the Ethical Treatment of Animals (Peta), posted a video on YouTube.com on Wednesday (20Aug14) showing him defacing a billboard in San Diego, California
Steve-O changed the sign to read 'Sea World Sucks' as a protest against the way killer whales are treated at the popular aquatic tourist attraction.
In the footage, which he titled Breaking the Law, the prankster says, "I'm putting my foot down for (whale) Shamu. If doing that was wrong, I don't want to be right! Screw you, SeaWorld!"
However, Steve-O may be facing legal troubles following his public confession. A representative for the California Highway Patrol has confirmed an investigation has been launched, telling Los Angeles news station Ktla the highway patrol was given "a case of alleged vandalism for investigation and possible prosecution in connection with the incident".
A statement from the California Department of Transportation adds, "We consider defacing public property at a cost to state taxpayers an unlawful act and a dangerous distraction for motorists. Not figured into the equation is the danger to highway workers and the inconvenience to motorists."
A spokesperson for the department adds the sign cost more than $7,000 (£4,118) to be replaced.
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