Colleen Mestas began her employment with the Visalia Police Department as an Assistant Chief of Police on July 7, 2008. In August of 2009, she became the Interim Chief of Police. In December of that year, Chief Mestas became the permanent Chief of Police of the Visalia Police Department.
Prior to her appointment as Assistant Chief of Police, Chief Mestas was employed with the Fresno County Sheriff Office since 1988 and was promoted to Captain in 2004. While assigned to the Fresno County Sheriff's office, she had oversight for the entire Patrol Operations Bureau, including SWAT, K9, Patrol Detectives, Ag-Task Force and Mounted Patrol. She also worked as a Patrol Deputy, Narcotics Detective, Field Training Officer, Patrol Sergeant, Lieutenant Watch Commander and Area Commander for Fresno's metropolitan region.
Chief Mestas holds a Bachelors of Arts Degree in Organizational Behavior from the University of San Francisco and a Master's Degree in Organizational Behavior from the California School of Professional Psychology. She is a graduate of the prestigious Senior Management Institute for Law Enforcement taught by Harvard University Scholars. She is also a graduate from the Marion Bergeson Series in Public Service and received certification from the Josephson Institute on Ethics in Law Enforcement and Police Administration.