Benefits of Knowing Your Defendant's IQ


Did you know that knowing the IQ score of the defendant you are representing can actually be of great benefit? When arguing that IQ is a significant cause of crime, researchers cite studies to indicate that criminal populations usually have an average IQ of approximately 92 which is eight points below the mean. The relationship between IQ and criminality is particularly distinct within a small portion of the population, primarily younger men, who are responsible for committing a disproportionate amount of crime while higher intelligence acts as protection against lapsing into criminal activity for people who are otherwise at risk.

From a sociological point of view, traits, such as the results of an IQ test are passed on genetically instead of through cultural transmission and are considered by many individuals to be both politically unfounded and empirically absurd. Due to this, a tremendous amount of controversy has been generated by researchers who argue that crime is based on low IQ with critics pointing out that crime rates vary significantly between generations and even within the same generation. Many criminologists argue that intellectually challenged individuals are not more likely to commit crimes and indicate that efforts to link IQ, genetics, biology and race to crime will result in repressive policy conclusions.

Using ‘Low IQ’ in the trial defense of Brendan Dassey

Since the Netflix documentary, 'Making of a Murderer' became a cult classic in 2015, mental health defenses, such as that of Brendan Dassey have been at the forefront of many debates pertaining to the various defense strategies of US lawyers and attorneys. Dassey, the nephew of Steven Avery, confessed to helping his uncle murder Teresa Halbach but later retracted his confession claiming that the details he provided investigators with were taken from the book ‘Kiss the Girls.’ The judge, William Duffin, overturned Dassey’s conviction on the grounds of it being coerced. He wrote that investigators made a number of false promises in exchange for a confession and that Dassey’s age, the absence of a supportive adult and his intellectual deficits meant that his confession was invalid. Dassey was 16 years old at the time and the results of an IQ test gave him a score of 70, putting him at 4th-grade level.

Types of mental health defenses

The three types of mental health defenses within the US legal system include competency, criminal responsibility and diminished capacity. Of the three, competency is argued the most as a defense tactic and focuses on the defendant’s mental limitations at the present time, as opposed to as at the time of the crime. Competency is a fundamental and constitutional prerequisite to the government when prosecuting a defendant. Simply stated, if the person is not deemed competent, the government cannot prosecute.

In 1960, the US Supreme Court decided the landmark case dealing with competency, the Dusky trial. The Supreme Court decided that it was unconstitutional to permit an incompetent person to stand trial because the individual is not competent to make a knowing, voluntary and intelligent decision about waiving the competency defense, the defendant cannot waive the defense. To comply with that requirement, the US criminal code contains a statute addressing the Dusky holding. This statute applies to a person with a very low IQ due to a developmental disability who may not understand the proceedings against them nor that their alleged conduct was wrong.

Using a low IQ score as a defense in court always has and always will remain extremely controversial. As long as mental incompetency pleas are allowed in the courts of the world, there will be arguments for it and arguments opposing it with no one but judge and jury having the power to decide whether the argument is valid or not.

TASA Article Disclaimer

This article discusses issues of general interest and does not give any specific legal or business advice pertaining to any specific circumstances.  Before acting upon any of its information, you should obtain appropriate advice from a lawyer or other qualified professional.

This article may not be duplicated, altered, distributed, saved, incorporated into another document or website, or otherwise modified without the permission of TASA and the author. Contact marketing@tasanet.com for any questions.

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