Ladue Police Chief Ken Andreski Jr. said he could not remember the last time his suburban St. Louis department had an officer-involved shooting in the town of about 8,600. The department has 26 commissioned officers.

Ladue officers began carrying Tasers sometime during the mid-2000s, said department spokeswoman Susan Ryan. The department rotated the devices among officers until last year, she said, when each officer was assigned their own Taser. Officers are trained annually, most recently in May last year.

A Taser — commonly known as a stun gun — is a weapon that fires barbs attached by wires to batteries that cause an electrical current to temporarily paralyze someone. The Taser can also be used directly on a person without firing the barbs.

Since 2001, there have been 15 known incidents where U.S. law enforcement officers said they mistook their service weapon for their stun gun and fired on a suspect, including one that occurred in a Pennsylvania police department holding cell in March, according to the Bucks County Courier Times. In three of the 15 cases nationwide, the suspects did not survive.

In all but four cases, including the March incident, the officer was not charged with a crime, according to the newspaper.