IQ and Criminal Psychology: Guest blog post

The following is a guest blog post by Allison Gamble. 

IQ and Criminal Psychology

During the early parts of the 20th century, the propensity to commit crimes was thought to have been defined by social class. People in lower classes often had less educational and financial opportunities and, as a result, committed more crime than their wealthier counterparts. Thus, those who studied forensic psychology quickly discovered that a correlation between crime and socioeconomic background could be made based not on IQ or the ability for learning but rather on the availability for opportunity to learn and therefore, succeed. 

For example, in the early 1900s people in lower classes often committed crimes purely out of necessity. In a social structure where socioeconomic differences are evident, it is common for those in the lower class to commit crimes to provide food or means of basic survival. While their IQs may be lower, this is more an affect of birthplace and right than of obvious mental impotence. The same could be assumed today were it not for the availability of social programs, which lessen, to a greater extent, the instances of abject poverty in most industrialized nations. 

However, the correlation between IQ and crime is still debated. In an abstract presented by the Department of Justice, the authors explain that those who commit a disproportionate amount of crime as compared to the rest of the population, share an intellectual level of about 98, with the mean score being around 106. Yet they also argue that a higher level of intelligence may offer a slight social insulation from moving into habitual criminal activities from early childhood into adult maturation.

As such, IQ tests are often used within judicial circles as a means of determining competency to stand trial. Yet, sadly, many offenders who are found to have a lower IQ score continue to be interrogated, tried and convicted for the crimes they may or may not have committed on a level not commensurate, some believe, with their understanding of their own conviction process. This is where IQ testing as it relates to the legal system is hotly debated. An article by Psychology Today, shows that suspects with a lower IQ score often falsely confess to crimes they have not committed due to lack of understanding on their part. 

These instances of false confession lead critics to believe that IQ assessments are perhaps being ignored outright or possibly even misused as a means of basis of conviction. A brief prepared by the New York State Court of Appeals, explains that there is frequently a correlation between suspects with a low IQ and a false confession. It is also noted that although these confessions occur more through coercion during intense interrogation, it appears that the suspects would not have confessed (matter the intensity of the interrogation) to their to the crimes they were accused of were it not for their misunderstanding of their situation. 

Due to the misuse of IQ assessments in the United States legal system, the Supreme Court ruled that certain individuals must have legal statutes as protections against the possible misuse of a general IQ test. These protections are meant to prevent employers, educators and the legal establishment from misusing an individual’s IQ assessment. 

However, criminals with higher IQs are not immune from prosecution once they are captured. Some experts even consider criminals with higher IQs to be more dangerous than those in the lower intelligence categories. When the IQs of serial killers, such as Ted Bundy, are they tested, they often are found to be above average. A study by Julietta Leung notes that the IQs of some serial killers are even considered to be on genius level. 

Sociology and Criminal Justice Professor James Oleson also studied the matter and found intriguing results that even the scales on both sides of the controversy. According to Oleson, criminals with higher IQs focus more on white-collar crime. Since these individuals come from backgrounds where financial resources are more prevalent, they are better able to evade detection and capture for a longer period of time no matter their crime. 

The use of IQ testing as the sole source for determining criminal propensity is controversial and unclear. As mentioned in an article from the University of Delaware, a direct correlation cannot be made between IQ level and criminal patterns or propensity. While IQ testing can show the likelihood of certain individual committing a crime, based on socioeconomic parallels, it cannot determine outright criminal intent nearly as well as a general personality profile, psychological evaluation or simple assessments of historical behaviors. Thus while IQ testing, as employed by the military, educational establishments and the legal system can prove to be a helpful aid in assessing the knowledge, skills and abilities of an individual; it cannot serve as the defining factor in the final adjudication of any individual.