COLUMBIA, S.C. - Gov. Mark Sanford may continue to serve in the Air Force Reserve, the state Supreme Court ruled Monday in throwing out a lawsuit claiming the governor was violating the constitution by being in the reserves.

Sanford's tenure as governor was challenged by Edward Sloan Jr., a retired businessman and self-described government watchdog who said the constitution allows the state's top officer to serve in and command only a state militia.

The court, which heard arguments in December, ruled unanimously that the term "militia" includes the modern reserves.

Sanford said he was grateful the court took up the issue.

"I've always viewed this decision as much bigger than me and I hope the court's ruling will help open the door to other folks in elected office who might want to be a part of the reserves," he said.

Sanford joined the reserves in January 2002, about two months before he filed to run for governor. He has said being in the reserves makes him a better governor and father to his four sons.

The first-term governor is in line for a promotion to captain in the Reserve's 315th Aeromedical Evacuation Squadron. About 40 percent of the 315th Wing has been called to active duty during the past year, but Sanford has not been among them.

Last April, Sanford completed two weeks of training at Maxwell Air Force Base in Alabama, and he has said he is working on a correspondence course designed to train him as a medical administrator.

Sloan said he may ask the high court to rehear the case. His attorney, Jim Carpenter, said he was disappointed the court didn't address his central argument: "That you can't be the commander in chief of one military unit, while simultaneously being ... in another military unit."