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FCI - Dr. John I. Thornton

Dr. John I. Thornton is a criminalist who studied directly under Dr. Paul L. Kirk (the father of modern forensic science). He is perhaps the most respected, accomplished, and well published forensic scientist in The United States. After a long career with many incarnations and retirements, he retired from work as a forensic scientists in late 2009.


From 1963-1972, John Thornton served as Criminalist with the Contra Costa Sheriff's Department in California.


From 1970-1994, he taught as a Professor of Forensic Science at the University of California, Berkeley.


From 1994-2003, he worked as a Forensic Scientist with Forensic Analytical Specialties, Inc. in California


From 204 until his final retirement, he served out the remaining years of his career working for the Napa County Sheriff’s Office (California), and as a Professor of Forensic Science at the University of California, Davis.


Dr. Thornton has twenty-two years of experience in an operational crime laboratory, four of them as a laboratory director, and twenty-four years of experience as a Professor of Forensic Science at the University of California, Berkeley. He testified as an expert witness on a wide variety of physical evidence. This owing to his extensive research and experience in the areas of evidence collection and processing, trace evidence analysis, firearms identification, gunshot residues, wound ballistics, bloodstain pattern interpretation, crime scene reconstruction, homicide investigation, ethics, and issues in expert testimony.

Over the decades, Dr. Thornton has quietly worked on a number of high Visibility Cases of international interest, including:


Peo. vs. Juan Corona (Yuba County) - 1972

Burden of Proof case – serial murders – farm labor contractor accused of killing 25 victims


U.S. vs. Jeffrey MacDonald (Ft. Bragg, NC) – 1979

Fatal Vision case – Army Green Beret doctor accused of killing his wife and children

Peo. vs. Randy Craft (Orange County) – 1988

Serial murders of 16+ victims


Peo. vs. Gerald Gallegos (Sacramento) – 1983

Sins of the Father Case – serial murder of 12 victims

Crown vs. Eastman (Australia) – 1995

Murder of second highest ranking police officer in Australia

Peo. vs. Joseph Hunt (San Mateo) – 1995

Billionaire Boys Club Case


Peo. vs. O.J. Simpson (Los Angeles) – 1997

U.S. vs. Terry Nichols (Denver) – 1998

Oklahoma City Bombing Case

Washington vs. Ridgway (Seattle) 2002

Green River Killer – serial murder of 49 victims


U.S. vs. Wuterich (Iraq) – 2007

Haditha Incident – 28 killed by US Marines

Apart from all of this, John Thornton was a mentor to Brent Turvey early in his career, during the late 1990s. As a mentor, Dr. Thornton listened, encouraged, and inspired, They published together on the subjects of crime reconstruction, trace evidence, and ethics. They also remain good friends.


The universal value of John Thornton's professional work, publications, and the example they set for future professionals are but a few of the reasons that The Forensic Criminology Institute is proud to name its library in his honor.

Dr. John I. Thornton's research is available at ResearchGate.


Without law there are no 

enforceable standards 

dealing with any scientific problem; without science there are no feasible 

means to resolve conflicts that inevitably accompany the many technical aspects of civilization. Law and  science have become bed-fellows.

- Dr. John Thornton

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