The 33-year-old "Terminator 3" star was arrested about 8 p.m. Thursday on Hollywood Boulevard.
He was booked on a misdemeanor count of lewd conduct and released from custody. The Los Angeles Times reports that Stahl was arrested at an adult movie shop during a routine undercover police operation.
In May, Stahl had been reported missing by his wife, but he later turned up. Stahl was a child star who performed in the 1993 film "The Man Without a Face."
He also has appeared in the 2003-2005 HBO series "Carnivale'" and starred in "Mirrors 2" in 2010. An email seeking comment from his publicist was not immediately returned Friday.
(Copyright 2012 by The Associated Press. All Rights Reserved.)