Northern Virginia police who spot drivers without seat belts began swapping polite warnings for fines more frequently this week in the run-up to the Memorial Day travel rush, part of a national campaign that has included TV ads, pitches to area students and gory refreshers on the physics of flying through windshields.

Participation in the "Click It or Ticket" campaign is part of Virginia's effort to spur compliance with state law requiring seat belt usage, said Virginia State Police Lt. Gary B. Payne. More officers will be on patrol through early next month to nab all types of offenders, he said.

"Your chances of being stopped for violation of the law are increased," Payne said, adding that motorists who get pulled over for speeding or another infringement can also get tagged with the seat belt fine. "We all can, from time to time, become complacent. We know there's enough data to know they save lives."

Two years ago, 438 of 913 people killed in motor vehicle accidents were unrestrained, according to Capt. J.F. Bowman, commander of the Fairfax County Police Department's traffic division. Seat belt usage in Virginia reached nearly 75 percent last year, according to state statistics.

"That's not bad, but it's not good," Bowman said, adding that some states are sharply higher. The rate in Washington state, for instance, is 95 percent, the highest in the country. Maryland is at 88 percent. "In the commonwealth, for every point we can increase seat belt usage, we'll save 12 lives," Bowman said.

Police have had to become adept at spotting sneaky motorists, Bowman said.

"We can tell if you've taken it off to get your wallet or purse," he said. "More often than not, we see someone reaching over to put it on."

Virginia, like 28 other states and U.S. territories tracked by federal researchers, allows police to issue seat belt citations only after stopping motorists for other infractions. Virginia officers can pull someone over if they see an unbelted child younger than 16.

State Del. Albert C. Eisenberg (D-Arlington) co-sponsored a bill earlier this year to allow police to ticket drivers solely on the basis of seat belts, known as a primary seat belt law. Opponents warned of the dangers of a creeping nanny state and defeated the effort.

"There is concern that if you have a primary seat belt law, that the police just have a license to stop anybody. People get concerned about impacts on minorities, et cetera," Eisenberg said.

But Eisenberg, who was U.S. deputy assistant secretary for transportation policy during the Clinton administration, argued that such laws are worth the potential trade-offs.

"There are enormous costs, in dollars and family loss and pain, because we don't have this law," Eisenberg said. "I'm sorry, we're not part of the frontier anymore, and we have to realize there are consequences when governments fail to enact laws to protect their citizens."

In communities throughout the region, enforcers are using a variety of strategies to encourage compliance with the law. Leesburg Police Lt. Brian Rourke sent a team of volunteers to crowded intersections to count cars and belt wearers to help come up with a benchmark for measuring the effectiveness of their campaign. The department is focusing special attention on trying to convert young drivers, Rourke said.

"I grew up never being in a car seat, and my parents didn't wear seat belts," Rourke said. He remembers standing with his face against the dashboard of his parents' car, a thought that he said gives him shivers now that he's a father. A new-driver class in high school changed his views, Rourke said, adding that he made his parents start putting on their belts.

"The didn't call it 'Click It or Ticket' then. It was simply driver's ed. It's a new face on an old picture," Rourke said. "Some people might think it sounds hokey, but . . . I like to think we're successful in the long run."

The seat belt fine is $25. Insurance carriers can also increase rates based on belt violations, Rourke said.