homehome Home chatchat Notifications


Brain scans are saving convicted murderers from death row–but should they?

Perpetrators of horrendous crimes could avoid the death penalty because of their brainwaves.

Michelle Petersen
February 23, 2022 @ 10:24 am

share Share

Over a decade ago, a brain-mapping technique known as a quantitative electroencephalogram (qEEG) was first used in a death penalty case, helping keep a convicted killer and serial child rapist off death row. It achieved this by swaying jurors that traumatic brain injury (TBI) had left him prone to impulsive violence.

In the years since, qEEG has remained in a weird stasis, inconsistently accepted in a small number of death penalty cases in the USA. In some trials, prosecutors fought it as junk science; in others, they raised no objections to the imaging: producing a case history built on sand. Still, this handful of test cases could signal a new era where the legal execution of humans becomes outlawed through science.

Quantifying criminal behavior to prevent it

As it stands, if science cannot quantify or explain every event or action in the universe, then we remain in chaos with the very fabric of life teetering on nothing but conjecture. But DNA evidentiary status aside, isn’t this what happens in a criminal court case? So why is it so hard to integrate verified neuroimaging into legal cases? Of course, one could make a solid argument that it would be easier to simply do away with barbaric death penalties and concentrate on stopping these awful crimes from occurring in the first instance, but this is a different debate.

The problem is more complex than it seems. Neuroimaging could be used not just to exempt the mentally ill from the death penalty but also to explain horrendous crimes to the victims or their families. And just as crucial, could governments start implementing measures to prevent this type of criminal behavior using electrotherapy or counseling to ‘rectify’ abnormal brain patterns? This could lead down some very slippery slopes.

Especially it’s not just death row cases that are questioning qEEG — nearly every injury lawsuit in the USA also now includes a TBI claim. With Magnetic Resonance Imaging (MRIs) and Computed tomography (CT) being generally expensive, lawyers are constantly seeking new ways to prove brain dysfunction. Readers should note that both of these neuroimaging techniques are viewed as more accurate than qEEG but can only provide a single, static image of the neurological condition – and thus provide no direct measurement of functional, ongoing brain activity.

In contrast, the cheaper and quicker qEEG testing purports to monitor active brain activity to diagnose many neurological conditions continuously and could one-day flag those more inclined to violence, enabling early interventional therapy sessions and one-to-one help, focusing on preventing the problem.

But until we can reach this sort of societal level, defense and human rights lawyers have been attempting to slowly phase out legal executions by using brain mapping – to explain why their convicted clients may have committed these crimes. Gradually moving from the consequences of mental illness and disorders to understanding these conditions more.

The sad case of Nikolas Cruz

But the questions surrounding this technology will soon be on trial again in the most high-profile death penalty case in decades: Florida vs. Nikolas Cruz. On the afternoon of February 14, 2018, Cruz opened fire on school children and staff at Marjory Stoneman Douglas High in Parkland when he was just 19 years of age. Now classed as the deadliest school shooting in the country’s history, the state charged the former Stoneman Douglas High student with the premeditated murder of 17 school children and staff and the attempted murder of a further seventeen people. 

With the sentencing expected in April 2022, Cruz’s defense lawyers have enlisted qEEG experts as part of their case to persuade jurors that brain defects should spare him the death penalty. The Broward State Attorney’s Office signaled in a court filing last month that it will challenge the technology and ask a judge to exclude the test results—not yet made public—from the case.

Cruz has already pleaded guilty to all charges, but a jury will now debate whether to hand down the death penalty or life in prison.

According to a court document filed recently, Cruz’s defense team intends to ask the jury to consider mitigating factors. These include his tumultuous family life, a long history of mental health disorders, brain damage caused by his mother’s drug addiction, and claims that a trusted peer sexually abused him—all expected to be verified using qEEG.

After reading the flurry of news reports on the upcoming case, one can’t help but wonder why, even without the use of qEEG, someone with a record of mental health issues at only 19 years old should be on death row. And as authorities and medical professionals were aware of Cruz’s problems, what were the preventative-based failings that led to him murdering seventeen individuals? Have these even been addressed or corrected? Unlikely.

On a positive note, prosecutors in several US counties have not opposed brain mapping testimony in more recent years. According to Dr. David Ross, CEO of NeuroPAs Global and qEEG expert, the reason is that more scientific papers and research over the years have validated the test’s reliability. Helping this technique gain broader use in the diagnosis and treatment of cognitive disorders, even though courts are still debating its effectiveness. “It’s hard to argue it’s not a scientifically valid tool to explore brain function,” Ross stated in an interview with the Miami Herald.

What exactly is a quantitative electroencephalogram (qEEG)?

To explain what a qEEG is, first, you must know what an electroencephalogram or EEG does. These provide the analog data for computerized qEEGs that record the electrical potential difference between two electrodes placed on the outside of the scalp. Multiple electrodes (generally >20) are connected in pairs to form various patterns called montages, resulting in a series of paired channels of EEG activity. The results appear as squiggly lines on paper—brain wave patterns that clinicians have used for decades to detect evidence of neurological problems.

More recently, trained professionals have computerized this data to create qEEG – translating raw EEG data using mathematical algorithms to help analyze brainwave frequencies. Clinicians then compare this statistical analysis against a database of standard or neurotypical brain types to discern those with abnormal brain function that could cause criminal behavior in death row cases.

While this can be true, results can still go awry due to incorrect electrode placement, unnatural imaging, inadequate band filtering, drowsiness, comparisons using incorrect control databases, and choice of timeframes. Furthermore, processing can yield a large number of clinically irrelevant data. These are some reasons that the usefulness of qEEG remains controversial despite the volume of published research. However, many of these discrepancies can be corrected by simply using trained medical professionals to operate the apparatus and interpret the data.

Just one case is disrupting the use of this novel technology

Yet, despite this easy correction, qEEG is not generally accepted by the relevant scientific community to diagnose traumatic brain injuries and is therefore inadmissible under Frye v. the United States. An archaic case from way back in 1923 based on a polygraph test, the trial came a mere 17-years after Cajal and Golgi won a Nobel Prize for producing slides and hand-drawn pictures of neurons in the brain.

Experts could also argue that a lie detector test (measuring blood pressure, pulse, respiration, and skin conductivity) is far removed from a machine monitoring brain activity. Furthermore, when the Court of Appeals of the District of Columbia decided on this lawsuit, qEEG didn’t exist. 

Applying the Frye standard, courts throughout the country have excluded qEEG evidence in the context of alleged brain trauma. For example, the Florida Supreme Court has formally noted that the relevant scientific community for purposes of Frye showed “qEEG is not a reliable method for determining brain damage and is not widely accepted by those who diagnose a neurologic disease or brain damage.” 

However, in a seminal paper covering the use of qEEG in cognitive disorders, the American Academy of Neurology (AAN) overall felt computer-assisted diagnosis using qEEG is an accurate, inexpensive, easy to handle tool that represents a valuable aid for diagnosing, evaluating, following up and predicting response to therapy — despite their opposition to the technology in this press. The paper also features other neurological associations validating the use of this technology.

The introduction of qEEg on death row was not that long ago

Only recently introduced, the technology was first deemed admissible in court during the death-penalty prosecution of Grady Nelson in 2010. Nelson stabbed his wife 61 times with a knife, then raped and stabbed her 11-year-old intellectually disabled daughter and her 9-year old son. The woman died, while her children survived. Documents state that Nelson’s wife found out he had been sexually abusing both children for many years and sought to keep them away from him.

Nelson’s defense argued that earlier brain damage had left him prone to impulsive behavior and violence. Prosecutors fought to strike the qEEG test from evidence, contending that the science was unproven and misused in this case.

“It was a lot of hocus pocus and bells and whistles, and it amounted to nothing,” the prosecutor on the case, Abbe Rifkin, stated. “When you look at the facts of the case, there was nothing impulsive about this murder.”

However, after hearing the testimony of Dr. Robert W. Thatcher, a multi-award-winning pioneer in qEEG analysis for the defense, Judge Hogan-Scola, found qEEG met the legal prerequisites for reliability. She based this on Frye and Daubert standards, two important cases involving the technology.

She allowed jurors to hear the qEEG report and even permitted Thatcher to present a computer slide show of Nelson’s brain with an explanation of the effects of frontal lobe damage at the sentencing phase. He testified that Nelson exhibited “sharp waves” in this region, typically seen in people with epilepsy – explaining that Grady doesn’t have epilepsy but does have a history of at least three TBIs, which could explain the abnormality seen in the EEG.  

Interpreting the data, Thatcher also told the court that the frontal lobes, located directly behind the forehead, regulate behavior. “When the frontal lobes are damaged, people have difficulty suppressing actions … and don’t understand the consequences of their actions,” Thatcher told ScienceInsider.

Jurors rejected the death penalty. Two jurors who agreed to be interviewed by a major national publication later categorically stated that the qEEG imaging and testimony influenced their decision.

“The moment this crime occurred, Grady had a broken brain,” his defense attorney, Terry Lenamon, said. “I think this is a huge step forward in explaining why people are broken—not excusing it. This is going to go a long way in mitigating death penalty sentences.”

On the other hand, Charles Epstein, a neurologist at Emory University in Atlanta, who testified for the prosecution, states that the qEEG data Thatcher presented flawed statistical analysis riddled with artifacts not naturally present in EEG imaging. Epstein adds that the sharp waves Thatcher reported may have been blips caused by the contraction of muscles in the head. “I treat people with head trauma all the time,” he says. “I never see this in people with head trauma.”

You can see Epstein’s point as it’s unclear whether these brain injuries occurred before or after Nelson brutally raped a 7-year old girl in 1991, after which he was granted probation and trained as a social worker.

All of which invokes the following questions: Firstly, do we need qEEG to state this person’s behavior is abnormal or that the legal system does not protect children and secondly, was the reaction of authorities in the 1991 case appropriate, let alone preventative?

As more mass shootings and other forms of extreme violence remain at relatively high levels in the United States, committed by younger and younger perpetrators flagged as loners and fantasists by the state mental healthcare systems they disappear into – it’s evident that sturdier preventative programs need to be implemented by governments worldwide. The worst has already occurred; our children are unprotected against dangerous predators and unaided when affected by their unstable and abusive environments, inappropriate social media, and TV.  

A potential beacon of hope, qEEG is already beginning to highlight the country’s broken socio-legal systems and the amount of work it will take to fix them. Attempting to humanize a diffracted court system that still disposes of the product of trauma and abuse like they’re nothing but waste, forcing the authorities to answer for their failings – and any science that can do this can’t be a bad thing.

share Share

Your Brain Has A Special Set of Neurons That Only Light Up for Music

Scientists have discovered unique neurons in the brain that respond only to music.

Why older adults are getting smarter than before: insights from new research

The cognitive gap between generations is narrowing.

How much of human intelligence is genetic versus acquired? Is it even possible to get smarter?

Intelligence, a blend of genetics and environment, centers on problem-solving abilities and is best enhanced through learning and formal education.

What do animals dream about?

Turns out, animals dream a lot like us: about everyday life.

Do we think in words or pictures?

It's a mix of both and much more.

Why we mix people's names: science says it's because you might care about them

It's perfectly normal to mix the names of loved ones. It's called a cognitive glitch.

The cocktail party effect -- our stunning ability to filter out words and sounds

It's a noisy world yet we somehow cope in the cocktail party of life.

Why are some people so competitive? The psychology of competitiveness

Exploring the fascinating psychology of a competitive person.

What chemicals make you happy?

Discover the science behind the happy chemicals in your brain.

Why serotonin makes you happy (or very, very sad)

Serotonin is a neurotransmitter in the brain that regulates mood and behavior and is associated with happiness and contentment.