Last week, a girl in the Bronx pulled out a can of pepper spray and used it in a fight with two other girls in her high school, an event that resulted in her arrest, her mother’s arrest and a report on WNBC.

The mother got locked up because she bought the stuff and gave it to her daughter, and the law in New York is strict about who can carry it — no teenagers, no felons — and how it is used. There was a long legislative fight over whether people should be allowed to carry it, and in 1996, New York became the last state to make it legal, over the objections of Mayor Rudolph W. Giuliani, who felt the rules were lax.

The law requires the following label to appear on the cans:

“The use of this substance or device for any purpose other than self-defense is a criminal offense under the law.”

Pepper spray is regulated with other dangerous weapons. For anyone interested in the effect it has on people hit with it, there are plenty of videos available online. You can hear agonizing screams, especially when it hits the mucous membranes and soft tissue like the eyes.