A law is limited if people don’t know about it, which is why the state has made an effort to publicize a measure intended to save the lives of police officers.

More than 170 law enforcement officers in the United States have died, and thousands have been injured, after being struck by vehicles since 1999, according a release from the Alabama Department of Public Safety.

So, the Alabama Legislature enacted a law in 2006 requiring motorists to move over one lane of traffic on four-lane roads, such as the interstate system.

When moving over is unsafe or not possible, the law requires drivers to slow to at least 15 mph below the posted speed limit. In areas where the posted speed limit is 20 mph or less, motorists must slow to 10 mph.

“To do our jobs, we must work in close proximity to traffic. The ‘move over’ law provides all first responders and emergency workers the clearance they need to work safely,” Col. Hugh B. McCall, director of the Department of Public Safety, said in the release.

Citations for violation of the “move over” law carry a fine of up to $25 for first offense, with increasing fines for second and subsequent offenses.

Alabama state troopers, along with officers in Florida and Georgia, worked last month to educate motorists.

Local law enforcement officials said the campaigns have made a difference.

“I think it has worked well,” Clanton Police Chief Brian Stilwell said. “It’s definitely a safety tool, especially since we have to work on (Interstate) 65.”

Chilton County Sheriff Kevin Davis said the law has made people realize the danger passing vehicles pose to officers on the side of the interstate.

“People just didn’t realize the danger,” he said. “We know we shouldn’t speed, but this wasn’t something that was in the minds of most people.”

Stilwell said he and other CPD officials have noticed a difference on I-65 recently while traveling back and forth from Montgomery.

“I can notice the people making an effort to get over in the left lane,” he said. “I think it’s getting better. A lot of the problems for us is people are so preoccupied that they’re just not paying attention.”