Fewer drivers were ticketed for violating Minnesota's mandatory seat-belt law during a recent enforcement campaign than in past years, indicating that more motorists are buckling up, authorities said Monday.

More than 12,000 motorists were ticketed for not wearing seat belts in the state's "Click It or Ticket" enforcement effort from late May to early June, dropping from nearly 15,000 during the same campaign in 2011.

In 2010, the total was 23,846. That was the first year the campaign coincided with allowing police to ticket motorists for seat-belt violations as a primary offense, rather than along with another misdeed such as speeding.

"We conduct these publicized campaigns to increase belt compliance with the goal to limit preventable deaths and injuries," Donna Berger, director of the Department of Public Safety's Office of Traffic Safety, said in a statement accompanying the tally. "Buckling up is the simplest, most effective precaution motorists have to stay safe on the road."

Education and enforcement seem to be having an effect, said Nathan Bowie, a spokesman for the Department of Public Safety. A University of Minnesota study published in March concluded that fatalities and serious injuries from car accidents have dropped "more than would have otherwise been predicted" since the law's implementation. Researchers said there were 68 fewer deaths, 320 fewer severe injuries and 432 fewer moderate injuries from June 2009 to June 2011.

Bowie said that while overall seat belt use seems to be going up, there are still those who aren't adhering to the law. The numbers remain low for teens and young adults, particularly young men. Of the 76 motorists between 15 and 24 years old who were killed, only 25 were buckled up, he said. Overall, 126 of 231 overall motorists killed in 2011 were wearing seat belts. As a result, the department is conducting education campaigns directed at younger drivers, employing social media and reaching out to high schools and universities. Seat belt use also remains low among those in rural areas.

The "Click It or Ticket" campaigns are a visible way to enforce the law, said Frank Douma, one of the university study's authors and the associate director of the state and local policy program at the University of Minnesota's Humphrey School of Public Affairs. The campaigns, which are national, are held each year in May and October.

"By coming out every six months and making it more visible, people are going to remember it," Douma said.

Seat-belt violations carry a $25 fine, but administration costs often push the total closer to $115, depending on the county where the ticket was issued.

The jurisdictions with the heaviest traffic saw the highest number of tickets issued. St. Paul was at the top (566). Next was Minneapolis (415). Outstate, St. Cloud police led the way (324).

An additional 301 citations were issued for child passenger safety seat violations, including for booster seats. St. Paul wrote 39 of these tickets, with Coon Rapids next at 28 and Minnetonka at 20.

Booster seats are the law for children who have outgrown a forward-facing restraint, for use until age 8 or until they are 4 feet 9 inches tall, whichever comes first. Boosters raise children so seat belts fit properly.

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