The State Bar of California receives complaints against attorneys, investigates those complaints, and disciplines attorneys. You may call their attorney complaint hotline at (800) 843-9053. The complaint form and more information about how to file a complaint can be found on their website: https://www.calbar.ca.gov/Attorneys/LawyerRegulation.
The District Attorney's Consumer and Environmental Protection Unit investigates and prosecutes unauthorized practitioners of law, including non-attorneys posing as attorneys and attorneys who have been disbarred. If you have reason to believe a person has engaged in the unauthorized practice of law, please call (805) 662-1750.