A U.S.-based cardiologist who provided expert testimony last year at the inquiry into the taser-related death of Polish immigrant Robert Dziekanski has some recommendations for police that could help lower the risk of killing someone with a stun gun.

However, Dr. Zian Tseng, an assistant professor in medicine at the University of California at San Francisco, stressed that police officers should be made aware of the potentially fatal consequences of using tasers.

“If you knew that the taser could potentially kill, obviously you wouldn’t pull it out as quickly as if you thought it was completely safe,” Tseng said in a phone interview with the Straight.

Tseng said that the high-voltage weapon has “almost zero” effect on the heart if it is not fired on a person’s chest area.

“The vector over the heart is very important,” he said. “So one practical recommendation would be is if it’s possible to avoid tasering the chest.”

Tseng said that it has been shown that the more times a police officer pulls the trigger of a taser, the longer that electrical pulses course through the recipient’s body. This increases the risk of the pulses “capturing the heart and affecting the heart rhythm”, he said.

Therefore, his second recommendation is that police officers should ease up on the trigger.

Tseng’s third recommendation is for police squads carrying tasers to be equipped with automated external defibrillators that can be used to revive a person who has been shocked with the weapon and suffered a cardiac arrest.

“These are very easy to obtain, they’re relatively inexpensive, and, in my opinion, if a police agency is using the taser, they should have the defibrillator available in case a cardiac arrest happens,” Tseng said.

Tseng added that these devices, which are about the size of a laptop computer, cost about $1,000 to $1,200.