What is Forensic Psychology?

Pop Culture Has Popularized This Niche Area of Study

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With numerous portrayals in books, movies and television programs, interest in forensic psychology has grown significantly in recent years. Increasing numbers of graduate programs offer dual degrees in psychology and law, with others providing specialization in forensic psychology. While forensic psychology was only recently recognized as a distinct specialization by the American Psychological Association, the origins of the field date back to Wilhelm Wundt's founding of the first psychology lab in Germany.

Learn more about some of the major events and key figures in this growing field in this brief history of forensic psychology:

Key People in the History of Forensic Psychology:

  • James McKeen Cattell – Studied the psychology of testimony.
  • Hugo Münsterberg – Often referred to as the father of applied psychology.
  • Alfred Binet – His work in psychological testing served as a basis for many modern assessments.
  • William Stern – Researched the accuracy of expert testimony.
  • William Marston – Testified at the trial that established the standard for expert witnesses.

Early Research in Forensic Psychology

J. McKeen Cattell conducted some of the earliest research on the psychology of testimony. He posed a series of questions to students at Columbia University, asking them to provide a response and rate their degree of confidence in their answer.. Cattell’s results indicated a surprising degree of inaccuracy, which generated interest among other psychologists who went on to conduct experiments on eyewitness testimony.

With even eyewitnesses being unsure of themselves, this raised serious issues about the validity of their usefulness in court. 

Inspired by Cattell's work, Alfred Binet replicated Cattell’s research and studied the results of other psychology experiments that applied to law and criminal justice. His work in intelligence testing was also important to the development of forensic psychology, as many future assessment tools were based on his work.

Psychologist William Stern also studied witnesses' ability to recall information. In one experiment, students were asked to summarize a dispute they witnessed between two classmates. Stern discovered that errors were common among the witnesses, concluding that emotions decrease the accuracy of witness recall. Stern continued to study issues surrounding testimony and later established the first academic journal devoted to applied psychology.

Forensic Psychology in the Courts:

During this time, psychologists were also beginning to act as expert witnesses in criminal trials throughout Europe. In 1896, a psychologist by the name of Albert von Schrenck-Notzing testified at a murder trial about the effects of suggestibility on witness testimony.

Hugo Munsterberg's ardent belief that psychology had practical applications in everyday life also contributed to the development of forensic psychology. In 1908, Munsterberg published his book On the Witness Stand, advocating the use of psychology in legal matters. Despite his contributions, Munsterberg was generally disliked by many of his peers in psychology and by much of the legal community.

Stanford psychologist Lewis Terman began applying psychology to law enforcement in 1916.

After revising Binet’s intelligence test, the new Stanford-Binet test was used to assess the intelligence of job candidates for law enforcement positions.

In 1917, psychologist William Marston  found that systolic blood pressure had a strong correlation to lying. This discovery would later lead to the design of the modern polygraph detector.

Marston testified in 1923 in the case of Frye vs. United States. This case is significant because it established the precedent for the use of expert witnesses in courts. The Federal Court of Appeals determined that a procedure, technique, or assessment must be generally accepted within its field in order to be used as evidence.

Post-WWII Growth:

Significant growth in American forensic psychology did not happen until after World War II. Psychologist served as expert witnesses, but only in trials that weren’t perceived as infringing on medical specialists, who were seen as more credible witnesses. In the 1940 case of the People vs. Hawthorne, the courts ruled that the standard for expert witnesses was in the extent of knowledge of a subject, not in whether or not the witness had a medical degree.

In the landmark 1954 case of Brown vs. Board of Education, several psychologists testified for both the plaintiffs and the defendants. Later, the courts gave support to psychologists serving as mental illness experts in the case of Jenkins vs. United States.

Forensic psychology has continued to grow and evolve during the past three decades. Increasing numbers of graduate programs offer dual degrees in psychology and law, while other offer specialized degrees emphasized forensic psychology. In 2001, the American Psychological Association officially recognized forensic psychology as a specialization within psychology.

Forensic Psychology Journals

  • American Journal of Forensic Psychology
  • Behavioral Sciences & the Law
  • Criminal Justice and Behavior
  • Journal of Forensic Psychology Practice
  • Law and Psychology Review
  • Psychology, Crime, & Law
  • Psychology, Public Policy, and Law


Bartol, C. R., & Bartol, A. M. (2005) History of Forensic Psychology. In I. B. Weiner & A. K. Hess (Ed.), The Handbook of Forensic Psychology (pp.1-27). Hoboken, NJ: Wiley.

Cattell, J. M. (1895). Measurements of the accuracy of recollection. Science, 2, 761–766.

Stern, L.W. (1939). The psychology of testimony. Journal of Abnormal and Social Psychology, 40, 3–20.

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