A new California law meant to boost gun safety, especially for teenagers and law enforcement, goes into effect on Jan. 1.

SB 199 requires BB and airsoft guns sold in the state to include fluorescent markings to distinguish them from real firearms. It was authored by Sen. Kevin de Leon, D-Los Angeles.

In several high-profile cases, police have shot teenagers after mistaking the toy guns the teens were carrying for real ones. In one case, a 13-year-old Santa Rosa boy was shot seven times by Sonoma County sheriff’s deputies after they mistook the airsoft gun the teen was carrying for an AK-47.

Democratic lawmakers passed the law more than a year ago, with the goal of preventing future tragedies.

Gun control advocate Mike McLively, an attorney at the Law Center to Prevent Gun Violence in San Francisco, said the law is a step in the right direction.

“A lot of these BB guns and airsoft guns are made to look extremely realistic these days,” the gun control advocate said. “So, it’s hard for law enforcement to distinguish between a fake gun and the real thing.”

Several police and health groups supported the law as it made its way through the Legislature in 2014.

The California Police Chiefs Association did not take an official position on the bill, but is generally supportive of it, said Rudy Escalante, chair of the association’s firearms committee.

“In the situation where a child has an imitation firearm, this may help the officer asses that situation,” added Escalante, police chief in the city of Capitola. “Imitation guns don’t belong in the streets where they endanger children and teens as well as law enforcement officers.”

Dave Givens is a youth shooting sports trainer in Merced County. He says the law won’t have much of an effect on his industry.

“The manufacturers, in an attempt to market to the younger shooters, have already offered their guns in a variety of different colors, patterns and camouflage schemes and so forth. It’s already part of the culture,” Givens said.

Gun control advocates, however, say the law should help phase out the toy guns that still look like real firearms.

The National Shooting Sports Foundation, a gun industry group, opposed the bill. A representative for the foundation declined to comment for this story. It told the Legislature last year that it was worried the new regulation would limit the availability of guns used to train young people in the safe handling of real firearms.