Greg Mandoli is a Special Agent with the Department of Homeland Security's Homeland Security Investigations (HSI) and is currently assigned to the US Embassy London. Previously, Greg was assigned to HSI’s Office International Affairs in Washington DC and the Office of Investigations in San Francisco. While in San Francisco, he participated in the Drug Enforcement Administration’s High Intensity Drug Trafficking Area (HIDTA) task force and the Federal Bureau of Investigation's Joint Terrorism Task Force (JTTF).

In 1991, Greg received his Bachelor of Arts degree in Business Economics with an emphasis in accounting from the University of California, Santa Barbara. In 1994, Greg graduated from Golden Gate University School of Law with the recognition of a Public Interest Law Scholar.

Before becoming a Special Agent, Greg practiced law as a deputy public defender in California where he handled felony matters involving homicide, Three Strikes, Gang and drug offenses. In 2006, Greg became the first HSI agent to graduate from the Naval Postgraduate's Master of Arts program in Homeland Defense and Security. His related professional activities include eight years as an Army Reservist in the Judge Advocate General Corps and current position as an Associate Adjunct Professor at the University of Maryland.