She received her Ph.D. in Criminology, Law and Society from the University of California, Irvine. Dr. Gardiner was awarded a prestigious National Institute of Justice Dissertation Fellowship to support her research on the effects of Proposition 36 on Orange County practitioners. Her areas of expertise include crime policy, policing, and juvenile delinquency. Her research has been published in Criminal Justice Policy Review and Journal of Drug Issues. Prior to her work at Cal State Fullerton, Dr. Gardiner worked as a police explorer, dispatcher, crime analyst, and intern-probation officer.