John Thomas Castle

Title: Forensic Toxicologist
Company: Castle Forensic Laboratory
Location: Dallas, Texas, United States

John Thomas Castle, a Forensic Toxicologist at Castle Forensic Laboratory, has been recognized by Marquis Who’s Who Top Scientists for dedication, achievements, and leadership in forensic toxicology.

Having accrued more than three decades of inimitable experience in his chosen field, Mr. Castle garnered a laudable reputation for his work as a forensic toxicologist. Having operated throughout the majority of his career in the region of Dallas, Texas, he specialized in chemical testing and serving as an expert witness in criminal cases where the defendant was accused of driving while under the influence of narcotics or alcohol. Attesting to the quality of work he provides, Mr. Castle worked on hundreds of occasions with local state and defense attorneys to exonerate their clients, and his expertise was sought in courts throughout all of Texas.

Well regarded for his professional longevity, Mr. Castle has notably been invited to speak at several conferences and symposia throughout the course of his career, having conducted seminars for the Dallas Bar Association and other legal service organizations. Moreover, he has spoken before audiences at the Indiana Law School between 1994 and 1995, and at the Percy Foreman Seminars in 1991. To remain aware of developments in the field, Mr. Castle maintained his affiliation with such organizations as the American Chemical Society, the Southwest Association of Toxicology and the Society of Forensic Toxicologists.

Mr. Castle initially became involved in his profession shortly after his departure from the U.S. Army, where he had served for eleven years. After attending courses in geology and physics at Texas A&M University, he availed himself of the opportunity to purchase several pieces of chemical lab equipment, through which he began his career as a forensic toxicologist. Eminently qualified in his field, Mr. Castle subsequently attained a Bachelor of Science in chemistry from Angelo State University, where he also attended graduate level classes.

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