It took a popular documentary “Making a Murderer” to have Brendan Dassey cleared of the crime after he spent 10 years in prison. His case sheds light on how the rights of mentally ill people are frequently violated in the justice system.

The Netflix documentary series chronicles the lives and trials of Dassey who was accused of helping his uncle, Steven Avery, murder Teresa Halbach in October 2005.

Dassey was 16 years old and reading at a fourth grade level. In March 2006 he spent four hours being interrogated by police without a parent or lawyer present. During his interrogation, he confessed to participating in both raping and murdering Halbach. As a result, Dassey spent the past 10 years behind bars, despite no evidence linking him to the crime other than his confession.

But a confession is a confession and innocent people don’t confess to crimes they don’t commit. Except when they do – and it happens a lot. This is why Dassey may be one of the luckiest men in the US on Friday; the national spotlight on his case may have given it the attention necessary to get a man with a learning disability and low IQ out of prison.

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Justice system flooded with people with mental illnesses

Those living with mental illnesses and disabilities begin on the wrong foot by being significantly more likely to end up being arrested. Nearly 2 million people with mental illnesses arrested every year, making an estimated 16.9 percent of jail detainees, according to The New England Journal of Medicine.

“The probability of being arrested was 67 percent greater for suspects exhibiting signs of mental disorder than for those who apparently were not mentally ill,” wrote Linda A. Teplin in a study for the National Institute of Justice.

There are many reasons for that, such as a lack of funding to public health or mental health outreach programs. Take Miami, for example, “it has the highest percentage of residents with serious mental illnesses, but Florida ranks 48th nationally in state funding for community mental health services” according to John K. Inglehart, a national correspondent of The New England Journal of Medicine.

The mentally disabled and ill are so prevalent in the Miami-Dade court system that Inglehart’s study quotes one judge as saying, “When I became a judge... I had no idea I would become the gatekeeper to the largest psychiatric facility in the State of Florida.”

Interrogation pressure

But for those suffering from disabilities or illness, they are in dangerous territory if they are considered suspects in crimes. “It is at this stage that persons with mental disabilities first suffer enhanced risk,” reads a paper from the American Bar Association titled Mental Health Status and Vulnerability to Police Interrogation Tactics.

This is indeed true. Typically the best advice people can receive about interrogation is to not speak without a lawyer present. The average person will hear about their Miranda rights in school, on the internet or through entertainment programs. However, that may be a common knowledge that a neuro-normal person may take for granted.

“The choice to avoid interrogation when not under arrest and to invoke Miranda when arrested is facilitated by understanding the potential dangers of the situation - an understanding that is compromised in those with impaired functioning in one or more psychological domains,” according to the ABA article.

In addition, it is not unheard of for police to suggest that a suspect’s silence will make them appear more guilty than talking, but the ABA says “they must control the need to confess simply as a way to end the interrogation, or satisfy the need for sleep, or to get the interrogators ‘out of my face.’”

Let’s go back to the interrogation Brendan Dassey experienced back in 2006. “Making a Murderer” shows arguments claiming that Dassey had an IQ range from 73 to 69, placing him between being borderline impaired or delayed or mildly delayed. Yet he was interrogated three times without legal representation present.

The ABA article states, “in two studies, 90 percent and 68 percent of adults with mental retardation received scores of zero on one or more tests of relevant vocabulary, understanding of the Miranda warnings, and understanding of the function of rights in interrogation (which was most poorly understood of all).”

Therefore, when he spoke with law enforcement and gave his confession, there is reason to believe that he understood neither his rights nor the implications of speaking with police.

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Interrogation is less about getting the truth and more about getting the confession, according to Brandon L. Garrett, professor at the University of Virginia School of Law. “What modern interrogation techniques do is convince the person the most rational and sensible thing to do is to confess,” he told Esquire.

A scene from Dassey’s interrogation shows a detective telling him: “I've got enough evidence without you. If you wanna help yourself, you have that opportunity right now to do that. Is that what you wanna do? Do you wanna help yourself? Then why are you lying? Look at me, Brendan.”

So here you have a juvenile being told that authorities know he’s involved and he needs to tell them that he is. This is where a false confession can begin.

Some people are more likely than others to make a false confession. Garrett explained to Esquire, “The bulk of the false confessions I've studied were either by juveniles or by people who are mentally ill or intellectually disabled. You'd expect people who are vulnerable to cave in to police pressure, and it's easier to put words in the mouth of a person like that.”

“The investigators repeatedly claimed to already know what happened on October 31 and assured Dassey that he had nothing to worry about,” Judge Duffin wrote in n the 91-page court order overturning Dassey’s conviction. “These repeated false promises, when considered in conjunction with all relevant factors, most especially Dassey’s age, intellectual deficits, and the absence of a supportive adult, rendered Dassey’s confession involuntary under the Fifth and Fourteenth Amendments.”

It’s not just Dassey

An investigation by the Chicago Tribune found that over the course of a decade, there were 247 examples of a defendant’s self-incriminating statements being thrown out of court for being tainted or juries did not find it convincing enough to convict.

“At least two dozen of the 247 defendants in the cases examined by the Tribune were mentally retarded, or had significant learning disabilities,” the Tribune noted.

The Innocence Project, a nonprofit dedicated to releasing the wrongly incarcerated, found that “more than one out of four people wrongfully convicted but later exonerated by DNA evidence made a false confession or incriminating statement.”

Here are the pieces of this. The mentally ill or disabled are the most likely to be arrested. If they are suspects in a crime, they are likely to be interrogated without counsel or understanding their rights. From there, it is easy to get a false confession out of someone without the mental faculties or education to know their rights or the best course of action.

Brendan Dassey is a free man now. So too are four out of the five exonerated men featured in “The Central Park Five,” who spent between six and thirteen years in prison for a brutal rape and attack that none of them were involved in. As were the West Memphis Three who spent years in prison after a teenage boy with a history of mental illness and disabilities gave a false confession that incriminated his two friends as well in the murder of three 8-year-old boys, famously featured in the HBO documentary series “Paradise Lost.”

These may be success stories, but one has to wonder how many other Brendan Dasseys will not be lucky enough to have a popular documentary help free them.