Dean Winters is an American actor known for playing Detective Brian Cassidy during the first season of Law & Order: Special Victims Unit. He also played Mike Stoat in Law & Order: Criminal Intent season seven episode "Purgatory".

Winters is also known for playing the character Ryan O'Reily on HBO's Oz, the same series in which SVU actors Christopher Meloni and B.D. Wong also appeared. Other guest appearances include roles in Homicide: Life on the Street, NYPD Blue, Sex and the City, Millennium, and CSI:Miami.

Winters was born in New York City and has three younger siblings, Bradford, Scott William, and a sister named Blair. Scott is also an actor, and portrayed Ryan's own brother Cyril on Oz.

He is currently the character "Mayhem" in The All-State commercials.


Law & Order: SVU as Detective / Officer / DA Investigator Brian Cassidy

Law & Order: CI


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