GDI began in 1997, when NYPD Detective Kevin Gannon was assigned to the disappearance of Patrick McNeill. Patrick had been missing 50 days when his body was found, 12 miles from where he was last seen. Gannon concluded that foul play was involved. He was taken off the case, and the death was ruled accidental.

Before he left, Gannon promised the McNeill family he would get justice for their son. That promise is why he came out of retirement. He joined two former NYPD partners, Tony Duarte and Mike Donovan, and the three set out to test a question the original files had never asked: how many similar deaths were also not accidents?

In 2014 the team published its first book, Case Studies in Drowning Forensics. When a body is recovered from water, investigators generally presume an accident or a suicide — the recovery site is rarely treated as a potential crime scene, and cases go unresolved as a result. The book examines 13 bodies recovered under similar circumstances, and one survivor. Built on field investigation and archival research, it was the first published work to present and explain the forensic autopsy evidence in these cases.

Book cover: Case Studies in Drowning Forensics by Kevin Gannon and D. Lee Gilbertson
The GDI investigators standing at a river dock at dusk, one pointing out across the water

The team

Kevin Gannon

Founder · Retired NYPD Detective Sergeant

Kevin Gannon spent 20 years with the New York City Police Department, serving as a Sergeant in the Detective Bureau. Over that career he made more than 1,000 felony apprehensions and was awarded almost 100 medals for bravery — retiring as the most highly decorated officer in NYPD history.

He commanded the Bronx Homicide Task Force and Nightwatch from 1999 until his retirement in 2001, and served on Operation I.C.E., Mayor Giuliani's 1997 task force for responding to a major chemical disaster or attack, which brought Department of Defense training in nuclear, biological, and chemical warfare. Gannon received the Medal of Valor twice, in 1994 and 1996, for heroism in the line of duty, and the National Gang Crime Research Center's Frederic Milton Thrasher Award in 2008 for his work on gang crime. He was previously featured on Dick Wolf's homicide series Dead Again.

Tony Duarte

Investigator · Surveillance & Data Research

Tony Duarte brings almost 21 years in law enforcement, built investigating homicide, robbery, burglary, and other high-profile crimes. He served on two major federal task forces targeting organized crime and was recognized with two awards from the U.S. Attorney's Office, 10 Excellence in Police Duty Awards, and five Commendations for Meritorious Service. Like Gannon, he received the Frederic Milton Thrasher Award in 2008 for gang crime investigation.

His technical specialty is data research and electronic audio-video surveillance. Duarte retired from the U.S. Department of Homeland Security, closing out his paid career in law enforcement — but he continues to work the cases that drew him to GDI.

Mike Donovan

Investigator · Interview & Interrogation

Mike Donovan is a retired NYPD Detective who worked alongside Gannon and Duarte for 20 years. His career ran from patrol officer in the Bronx to the Organized Crime Control Bureau's elite anti-narcotics unit, and finally to the Detective Bureau, where he investigated hundreds of homicides. He was among the first responders at the World Trade Center on September 11, 2001.

Donovan's specialty is the interview room. He reads character and body language, and has a long record of getting witnesses to say more than they realized they knew.

D. Lee 'Doc' Gilbertson

Ph.D. · Forensic Victimology & Crime Analysis

Dr. Gilbertson holds a doctorate in Sociology, with a concentration in gangs and substance abuse, and a Master of Science in Criminal Justice focused on criminology and victimology. He served 16 years in the military, in infantry and signals intelligence, from 1976 to 1992.

He teaches at Saint Cloud State University and has consulted with law enforcement agencies and delivered training in forensic victimology, crime analysis, and gangs. A certified gang specialist who has studied gangs, militias, and extremist groups since 1995, Gilbertson is a staff member of the National Gang Crime Research Center, an Executive Editor for the Journal of Gang Research, and a three-time recipient of the Frederic Milton Thrasher Award.

The GDI investigators reviewing case files together at a round table