Study: Cops should wait to question Tased suspects

It seems unsurprising that getting zapped by a Taser might scramble your brains a bit.

But such cognitive impairment could affect a person's ability to understand his or her constitutional rights at the point of arrest - and should prompt police departments to wait longer before interviewing a stun-gunned suspect, according to new study by Drexel University and Arizona State University researchers.

The study, "TASER Exposure and Cognitive Impairment: Implications for Valid Miranda Waivers and the Timing of Police Custodial Interrogations," was published this month in the journal Criminology & Public Policy. The U.S. Department of Justice's National Institute of Justice funded the study.

Supporters laud stun guns as a less-lethal tool than handguns and other weapons police can use to disable a resisting suspect. Police in 17,000 departments have Tased more than two million people across the United States during the past decade, the study found.

But a 50,000-volt jolt to the brain hurts a person's ability to remember, concentrate and process information and heightens anxiety, researchers found.

In clinical trials, the researchers subjected 73 study participants to Taser shocks. One finding was almost universal, according to one of the study's lead investigators. "Everybody screamed when they got Tased, and most people said the F word as well," said Robert J. Kane, a professor and head of Drexel's Criminology and Justice Studies Department.

Beyond that, Kane and his colleagues found that many of those Tased showed short-term but severe declines in cognitive functioning, comparable to dementia. The effects lasted, on average, less than an hour - although a few participants didn't get fully back to normal for up to a week, Kane added.

And a Taser's effects might be worse outside of the science lab, Kane warned.

Study participants were college students, or "healthy, highly intelligent test-takers" who generally function at a higher level of cognition than suspects on the street, who might be mentally ill, high, drunk or just generally unhealthy, Kane said.

Because the things a suspect says to a detective can haunt him for life, Kane said his study should launch a discussion about public policy.

Kane's takeaway: Police should wait an hour before interrogating stun-gunned suspects, whose muddled minds could lead to false confessions or other statements they wouldn't make when they're thinking clearly.

"Here's the problem: Despite what the Supreme Court has said on numerous occasions - that they would like police to develop more investigative strategies than using suspects' statements and confessions as evidence - police still often rely on the confession as the primary evidence in cases they build," Kane said.

Kane added: "I think the Taser is a remarkable device that has probably saved a lot of lives. As an alternative to deadly force, there are few better options to deploy in the field. But if it's going to be deployed, we should better understand how its use affects our abilities to exercise our constitutional rights."