Forensic Psychology Fact and Fiction

Forensic psychology is probably one of the most misunderstood fields in psychology. Television shows and movies depict extraordinary individuals with psychic abilities who scan crime scenes and quickly deduce who committed the crime, or briefly interview suspects and know if they are lying.

In fact, forensic psychologists apply evidence-based psychological knowledge to support the criminal justice system, such as solving crimes and assessing risks of violence. Importantly, they also understand that many of the tools and methods they use are not infallible. For example, while TV shows/movies may depict forensic psychologists assessing whether someone is lying, a real forensic psychologist will know that there is no 100% accurate way to detect lies. In fact, research shows that the public and law enforcement may be much worse at detecting lies than they think.

polygraph

Research shows that in tests, most people perform at chance level (i.e., the decision to flip a coin is equally accurate) when trying to determine whether someone is dishonest. Still, research also shows that many people, especially law enforcement officers, are confident in their polygraph abilities.

There has been little research on the police in Australia, but a large-scale study published in 2011 found that police officers, particularly detectives, were very confident in their lie-detection abilities, but many used methods that forensic psychology research showed were unreliable and could lead to false convictions.

It is important to share scientific research on polygraph detection with law enforcement and to educate the public about forensic psychology research because one day they may be able to make credible decisions that, if they serve on a jury, could severely impact another person and the entire community. That’s why it’s important for forensic psychologists (and psychologists in general) to stay up to date on the latest research, and why some people interested in forensic psychology decide to become researchers.

When studying forensic psychology, it is helpful to examine the history of specific procedures and tools because this can show how harmful overreliance on assumptions about accuracy can be. It can also highlight that some tools are developed with biases or stereotypes. An historical example is profiling, as seen in the witch-hunts of early modern Europe.

Historical applications of criminal profiling

Criminal profiling involves identifying the characteristics of a criminal based on the type of crime and/or crime scene. Around 1486, two monks published a Latin book called Malleus Maleficarum (English: “The Witch’s Hammer”). This book is designed to help identify, prosecute, and punish witches. According to the book, many, if not most, women are evil, and witches are said to be identifiable.

Witches are primarily described as women with the following characteristics:

1. Spots, scars or birthmarks, sometimes on the genitals, sometimes invisible to the inquisitor’s eye
2. Live alone and keep pets (a demon in animal form, called a familiar)
3. Symptoms of mental illness (auditory or visual hallucinations, etc.)
4. Planting medicinal materials
5. no children

No proof is needed that someone is a witch. If the plaintiff is credible (e.g., an upstanding citizen of the community), their word is sufficient. Anyone who attempts to defend an accused witch (i.e. state that the person is not a witch) is considered an accomplice. Witches were tortured and killed (e.g., burned at the stake).

Think about it, if you are a woman, how many of these criteria have you met now or in the past? Think about the women you know. How many fit some or all of these criteria? Shockingly, in some countries some people still believe in witches and “witch lynchings,” killings without formal trials, still occur. Another area of ​​forensic psychology related to criminal profiling is the study of personality and crime, which develops from the questionable past.

Personality and crime

Personality is defined as an enduring and stable pattern of thoughts, feelings, and behaviors. While doctors and philosophers in ancient Greece and China described specific characteristics of certain people, arguably the most widely popular theory of personality and its connection to deviant behavior and criminal behavior was phrenology.

Dr. Franz Gall, a German-born physician and scholar, introduced so-called phrenology to Europe in the early 19th century. Vienna’s largest hospital and adjoining lunatic asylum were built, and Gall attended Vienna Medical College. Gall is part of a large academic community interested in cognition (e.g., how people think, remember, acquire knowledge, and make decisions).

The prevailing theory at the time was that all cognitive processes involved whole-brain activity. Gall developed the idea from studies of animal behavior that different human behaviors result from the functioning of different “brain organs.” Gall noted that people with similar abilities and/or characteristics share similar facial and cranial features (e.g., protruding eyes and excellent memory). Gall speculates that this is no coincidence. Gall had access to hospitals and asylums and, after befriending the Vienna police minister, prison.

Gall then studied the facial and cranial features of mentally disturbed and antisocial individuals, such as murderers, who were residents or detainees in these facilities. He began making postmortem (post-mortem) observations around 1792 and began collecting skulls of the dead (and making wax and plaster casts). Ten years later, Gall collected the skulls of 300 people, many of them criminals.

Gall proposed a theory of brain physiology that explains human behavior, ranging from exemplary behavior (e.g., nobility, generosity, intelligence, and kindness) to deviant behavior (e.g., dishonesty, cruelty, and crime). He created a list of 27 human behaviors that could be observed (either through senses or vision) through analysis of the face and skull. Gall’s theory is considered scientific because it involves a comparison of observable and recordable skull shape and behavior. He spoke and wrote extensively about his ideas.

However, in 1801 Emperor Franz II banned Gall’s publications and lectures, citing moral and religious concerns. The ban had the opposite intended effect. From 1802 onwards, growing curiosity about Gall’s theories led him to begin lecturing throughout Europe in 1805. Gall became internationally renowned and phrenology spread throughout Europe. By the 1830s, phrenological books, pamphlets and societies had spread across Britain. Phrenology soon spread to other countries.

Phrenology provides a very high-paying career for practitioners, many of whom have no training. Phrenologists offer free lectures and advertise paid private readings to those who want to know information about others (for example, parents planning who their daughter will marry). Phrenologists profited from an unscientific method of determining human personality and likely behavior.

Phrenology is considered scientific, but like other methods of predicting people’s likely behavior, such as astrology, it lacks scientific rigor. For example, many doctors investigated Gall’s claims by examining patients’ heads and discovered inaccuracies in phrenology. Gall dismissed the doctors’ claims and supported only evidence supporting his theory. Eventually, the phrenologists’ claims were proven wrong, and the oversales of phrenology preempted its demise.

However, phrenology was a groundbreaking discovery in understanding human cognition: different areas of the brain are involved in different behaviors and abilities. Additionally, research on personality disorders and crime shows that people with antisocial personality disorder and psychopathy are more likely to commit crimes than people without these disorders. This area of ​​research has been expanding since Fazel and Danesh (2002) found, in a review of nearly 23,000 offenders, that 65% of men and 47% of women were identified as having one or more personality disorders.

While we shouldn’t predict who a criminal is by assessing head impacts, research shows that if you’re trying to predict criminal behavior, assessing whether someone is a psychopath or has antisocial personality disorder can be helpful.

Advice for people interested in becoming a forensic psychologist

Modern forensic psychology is evidence-based and critical thinking is an important skill to master. History shows how dangerous an unsupported approach can be, and those interested in becoming a forensic psychologist can take the first step by developing critical thinking skills and learning the scientific method.

If someone is interested in becoming a forensic psychologist, the process in Australia involves completing an undergraduate degree in psychology or a double major in psychology and criminology (3 years), followed by a one-year honors degree, after which students complete a two-year master’s degree in forensic psychology. If someone wants to become a forensic psychology researcher and academic (i.e. a university lecturer who conducts research), they can complete a PhD (3-4 years) instead of a master’s degree.

While the learning journey is long, forensic psychology is a fascinating field and an exciting area of ​​study, with much still to be discovered. If someone decides to become a forensic psychology researcher, my personal experience leads me to believe that they will never be bored.

Dr Rebecca Wilcoxson is a Lecturer in Forensic and Social Psychology in the School of Health, Medical and Applied Sciences at Central Queensland University, Australia. Her main area of ​​research is lie detection.