Charlie Gilbert was recruited by GDBA from the Central Intelligence Agency, where he served in the Top-10 leadership position of Deputy Director of the National Clandestine Service.

One of the world’s true experts on protection, James Hamilton was recruited from the FBI, where he developed the Academy’s Protection Course, currently taught to protectors of the U.S. Attorney General and Director of the FBI, as well as protectors at NSA, and many other agencies.

Gabrielle Thompson, PI, CPP, is a leading behavioral scientist specializing in threat assessment. For more than 20 years, she has managed thousands of cases involving unwanted pursuit and threats. Gabrielle is Senior Instructor at The Advanced Threat Assessment Academy.

Before John Muffler joined GDBA, he served as Chief of Domestic Operations for the U.S. Marshals Service, and Chief Inspector of the National Center for Judicial Security.  At the Federal Law Enforcement Training Center, he taught protective operations, threat assessment, and protective intelligence.  John is a member of the Department of State’s Fulbright Specialist Program.

Bryan Niederhelm has managed some of the Nation's most sensitive threat assessments. Prior to joining GDBA, he served in a special U.S. Marine battalion, protecting U.S. Diplomats and Top Secret information, and providing security and logistical support for U.S. presidents.

During his career with the United States Secret Service (1983-2003), Vincent protected two U.S. Presidents and other heads of state, and rose to several leadership positions. He was then appointed to the senior-most security position at the International Monetary Fund, where he served until being recruited by GDBA in 2023.

For more than 20 years, Fritz Allen has designed protective security strategies for at-risk individuals and led protection operations throughout the world. Prior to joining GDBA, Fritz served in the United States Marine Corps.

Ellen Prystajko is a behavioral scientist with a specialty in threat assessment. She has managed thousands of cases involving threats, unwanted pursuit, and workplace violence, and served on the Development Team for several MOSAIC Threat Assessment systems.

Michael LaFever has advised our high-risk clients since 1979. He is the firm’s liaison with LAPD, U.S. Department of State, Department of Defense, Secret Service, and various international law enforcement agencies. Michael was the only civilian attendee at the Central Intelligence Agency’s first Threat Management Conference.