New ASU Study Shows Taser Use Temporarily Impairs Brain Function

Published: Thursday, April 9, 2015 - 6:02pm
Updated: Thursday, April 9, 2015 - 8:30pm
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(Photo courtesy of Casey Kuhn)
A Taser used by the Tempe Police Department.
(Photo courtesy of Casey Kuhn)
Tasers fire two dart-like electrodes contained in these cartridges.
(Photo courtesy of Casey Kuhn)
A Tempe police officer tests the electric charge in a Taser.

With the spotlight on police shootings around the country, many departments are relying more heavily on so-called “less than lethal” force to subdue arrestees. New research shows the effects of Tasers may last longer than previously thought.

The Miranda warning is something you don’t want to hear. It’s the result of a 1966 Supreme Court Case that began in Phoenix. Now all officers nationwide are required to read the famous lines to an arrestee after they’ve been taken into custody. An arrestee can waive those rights as long as they demonstrate a basic understanding of the warning, but new research may cast some doubt on a defendant’s ability to meet that standard.

Chris Hannigan received a Taser exposure as part of his training to become an officer with the Tempe Police Department. After catching his breath, he said he’s OK, but not everyone recovers from the experience the same way.

”I saw a number of individuals cry," said Dr. Michael White, a professor of criminology and criminal justice at Arizona State University. "There’s a very strong, emotional response.”

White is the lead author of a forthcoming study from the journal Applied Cognitive Psychology examining the effects of Taser exposure on cognitive functioning. 

After completing a pilot study of 21 police recruits, White and his team recruited close to 800 ASU students for a randomized trial. Some of the students served as a control and were given no treatment, while others were actually subjected to a five-second Taser exposure. All of the students were given a battery of mental and physical tests before and after the exposure. 

While all of the participants returned to their baseline testing levels within 24 hours, White found statistically significant declines in cognitive function and memory in the Tased students for up to an hour after their exposure.

White thinks this could have implications for arrestees that waive their Miranda rights and offer a confession during this time of impairment.

When deciding whether or not to allow a confession, a judge takes into account many factors. This is called the “totality of circumstances.” For example, an arrestee might give up information while intoxicated or they may not speak English and can’t understand the Miranda warning.  

Even then, Yale Law School Professor Steven Duke said it’s pretty tough to get a confession thrown out.

“About the only people that have a shot at having their confessions excluded are those people who are grossly mentally or emotionally impaired," Duke said.

But Dr. White said that’s exactly what he witnessed, time and time again.

”In some cases, you could visibly see how people were affected by the Taser exposure," he said.

White said aside from being emotionally shaken, participants were unable to repeat back lists of words and displayed significant loss of memory. 

"Certainly the fact that we’re seeing some disruption, that it’s temporary, I think raises questions about the reading and waiver of Miranda rights within that one-hour mark," White said.

Jean-Jacques Cabou is a Phoenix-based criminal defense attorney. He said when defendants waive their Miranda rights and offer information to police officers, their waiver must follow certain criteria.

”The courts have set forth a standard by which criminal defendants’ choice to waive any of their rights is evaluated," he said. "And they ask whether the waiver is knowing, whether it’s voluntary and whether it’s intelligent.”

While Cabou admits there’s a high bar to have confessions thrown out, he said the new study could affect how a court interprets a knowing and intelligent waiver.

”There are arguments to be made that someone could be pushed below the threshold of intelligence or knowledge as the result of being Tased," Cabou said.

White’s team tried replicate the conditions of a contested arrest by having study participants engage in physical activity before their Tasing, but he admits young healthy college students are not the best sample of the average arrestee.

He said the next step will be to try to work with local police departments to test cognitive functioning of actual arrestees after they have been Tased in the field. 

Professor Duke is skeptical of any Miranda policy changes in the near future.

“All sorts of cognitive impairments are commonly present when people are questioned by the police and it almost never results in the exclusion of their incriminating statements," Duke said.

He said if you’re detained, the best course of action is to invoke your right to remain silent and get a lawyer.

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