COLUMBIA, S.C. - A stronger seat belt bill allowing police to pull over adult drivers solely for not wearing their seat belt has become law after Gov. Mark Sanford did not veto it by midnight Wednesday.

Senate Clerk Jeff Gossett said early Thursday morning the governor did not send him his veto, meaning either Sanford signed the bill or let it become law without his signature.

The governor's office did not return a phone message early Thursday morning to say what Sanford decided to do with the bill or explain his decision.

The state already requires drivers and passengers to wear seat belts. However, police currently can only ticket adult drivers for the offense if they are pulled over for another violation. Police can stop cars when children or drivers younger than 18 aren't wearing seat belts.

The new law will let police pull a driver over simply for not buckling up. A compromise between the House and Senate sets a $25 fine for seat belt offenses with no points on a driver's record.

Sanford had said he planned to veto the bill because its penalties were not harsh enough, but after it passed last week, his spokesman said he would take a close look at the legislation. The governor has scheduled a news conference for 10:45 a.m. Thursday to discuss his decision.

Sanford had said he wanted a bill that allowed a conviction for failing to buckle up to be a factor in injury lawsuits as well as causing repeat offenders to pay more for car insurance.

A stronger seat belt bill has been a hot topic in the Legislature for two years. In 2004, a bill was bottled up by a few senators who said forcing people to wear seat belts infringed on their personal freedoms.

As a compromise, lawmakers agreed to ban the issuing of seat belt tickers at traffic checkpoints, like the "Click It or Ticket" campaign periodically conducted around the state.

The law says police can't search cars at seat belt stops and requires the state to create a public database that could be used to show whether police use race as a factor in pulling people over for not wearing seat belts.

When the new law goes into effect, South Carolina will join about 20 other states with a primary seat belt law, according to Mothers Against Drunk Driving.

State Public Safety Department statistics show that 267 of 363 motor vehicle occupants who died this year as of June 5 were not wearing seat belts.