Mr. Rosato started his legal career as a Los Angeles Public Defender after graduating from UCLA School of Law.

Mr Rosato entered private practice as a sole practitioner handling all manner of criminal and civil cases. He also had the opportunity to be selected to sit as a judge Pro Tem in the Superior Court.

Mr. Rosato was the Senior partner in his own firm, Rosato & Samuel, PC, supervising 17 attorneys and handling all manner of litigation. Primarily an insurance defense practice, major clients included Blue Cross of California, Cigna Insurance, Farmers Insurance Group of Companies, AIG Insurance and Foundation Health. Mr. Rosato retired from the practice of law in 1996 spending his time teaching and traveling. He joined the Los Angeles County Counsel's office in 2000.

Mr. Rosato is currently an Assistant County Counsel for Los Angeles County and is the Division Chief of the General Litigation Division handling litigation on behalf of the County of Los Angeles.