TMZ: 'Shameless' star Ethan Cutkosky arrested for DUI

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The guy who plays one of the troubled Gallagher kids on "Shameless" ran into some real life trouble off set, getting busted for a DUI, TMZ has learned.

Ethan Cutkosky, 18, who plays William Macy's second youngest child on the show, was arrested and booked for DUI Thursday in the Los Angeles area.

Law enforcement sources said Ethan was driving his orange BMW at around 10:30 p.m. and began to straddle the traffic lanes, which prompted cops to pull him over.

Law enforcement said officers smelled marijuana in the car during the stop, and TMZ sources said Ethan admitted he'd been smoking weed that night. Police drew Ethan's blood for toxicology testing, which is pending.

TMZ is told he did poorly on field sobriety tests and was arrested on the spot. TMZ reached out to Ethan's representatives who had no comment.

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