COLUMBIA -- Buckle up or pay $25.

That's the message of a new South Carolina law that allows police officers to pull over adult drivers if anyone in the car is not wearing a seat belt. Under the old law, officers could ticket adult drivers for seat-belt violations only if the car first was stopped for another offense.

Gov. Mark Sanford allowed the bill to become law without his signature Wednesday after hinting for weeks that he would veto the bill. Sanford said he decided not to veto the measure because it merely strengthens a "well-intentioned, but flawed" law that has been on the books since 1989.

"I don't like this bill. I've been clear on that," Sanford said. But, "I think that my real role is to enforce the laws that are created by the legislative branch -- some I'll like, some I won't like."

The new law takes effect six months from June 9 and imposes a $25 fine for not wearing a seat belt. The law bars seat-belt citations from being reported to insurance companies or being used as evidence in court.

Those provisions, along with the $25 fine, weaken the law, Sanford said, making it unlikely to encourage drivers to wear seat belts.

"I would anticipate that this bill would not prove the results that people are looking for," Sanford said.

Though he strongly advocates the use of seat belts, Beaufort County Sheriff P.J. Tanner has aired several concerns about the legislation. He's predicted tricky court battles with people who have been ticketed, and charges that the police are using the law to target people unfairly.

With the legislation passed, however, Tanner said it was time to set aside those concerns and enforce the law as written.

"When the bill turns into law, then it becomes my job to enforce it, regardless of how I feel about it," he said. "Do I foresee debates? Sure I do."

Jury trials are likely to involve debates about clothing, seat-belt colors, tinted windows and other factors making the strap hard to see, he said. He also has predicted charges of racial profiling, an issue the law tries to address by setting up a database to show whether police use race as a factor in pulling over people who do not wear seat belts.

Police will have to gather data on race, gender and age at traffic stops even if a ticket is not issued.

Advocates say the new law will save lives. State Public Safety Department statistics show that 269 of 365 motor vehicle occupants who died so far this year were not wearing seat belts, agency spokesman Sid Gaulden said.

"In a lot of cases, unbelted people are ejected," said Donna Carter, state chairwoman for the South Carolina chapter of Mothers Against Drunk Driving. "A lot of injuries are sustained once the body leaves the car, and they're most of the time fatal."

South Carolina will join about 20 other states with primary enforcement of their seat-belt laws, according to Mothers Against Drunk Driving.

The law should save about 50 to 80 lives within the first year in South Carolina, said Max Young, who heads the Public Safety Department's Office of Highway Safety.

In other states that have enforced such laws, seat-belt use has gone up by about 10 percentage points and statistics show that five to eight lives are saved for every percentage point increase in usage, Young said.

If the same holds true for South Carolina, seat-belt use should go up to 76 percent. "That's what I'm hoping for or even higher," Young said.

Legislators have tried for the past two years to strengthen the state's seat-belt law. In 2004, a bill was bottled up by a few senators who said forcing people to wear seat belts infringed on their personal freedoms.