Cassidy's attorney, Steven Graff Levine, entered an open plea to a Los Angeles judge Monday, admitting that the 63-year-old singer-actor was driving under the influence when he was arrested in January after making an illegal turn.
Levine says Cassidy has been in rehab and will remain for longer than his sentence requires. He says Cassidy is committed to his sobriety and wants to break the cycle that got him arrested for drunken driving twice in less than six months.
A DUI case in New York was reduced from a felony to misdemeanor earlier this month.
Cassidy was also previously arrested in Florida in 2012 on another DUI charge.
Cassidy appeared as Keith Partridge on TV's "The Partridge Family" from 1970-1974.