COLUMBIA, S.C. — Legislators, not the legal system, should handle citizen complaints against their elected representatives, South Carolina’s highest court ruled Wednesday, turning down a case accusing Gov. Nikki Haley of breaking ethics laws.

The state Supreme Court ruled against Republican activist John Rainey, who sued Haley in 2011. He accused the GOP governor of improper lobbying while working as a hospital fundraiser and for a highway engineering firm while representing Lexington in the state House.

The complaint also asked whether it was illegal for Haley to seek tens of thousands of dollars from lobbyists for the hospital’s foundation while legislators were in session.

A judge threw out Rainey’s case, which he appealed. Rainey also lodged a parallel complaint with a House ethics panel, which ultimately cleared Haley of all allegations last summer after its first inquiry into a sitting governor.

At the hearing, Haley told lawmakers she did nothing wrong in her job as a fundraiser for a nonprofit organization that funds Lexington Medical Center’s health care programs. She also worked as a consultant for engineering firm Wilbur Smith Associates.

It’s that legislative venue, the high court said Wednesday, that should have received the complaint in the first place.

“The House and Senate Legislative Ethics Committees are charged with the exclusive responsibility for the handling of ethics complaints involving members of the General Assembly and their staff,” the court wrote. “A court’s exercise of jurisdiction over appellant’s ethical complaint against Gov. Haley would not only contravene the clear language of the State Ethics Act, it would also violate separation of powers.”

South Carolina courts are empowered to hear ethics complaints if an election is happening in 50 days, a timeframe not directly relevant to Rainey’s case.

Haley’s office has called the suit a political vendetta and a waste of taxpayer money. During last summer’s hearing, the governor — the state’s first woman and first minority governor — called Rainey a “racist, sexist bigot” for comments he made to her during her 2010 gubernatorial bid. Haley, the child of immigrants from India, said Rainey insulted her family when he told her he didn’t want to back her for governor, only to discover later that she was related to terrorists.

Rainey, who convinced former Gov. Mark Sanford to run years ago and later was his Board of Economic Advisors chairman, said he wanted to ensure the next candidate he backed didn’t wind up in a scandal, as Sanford did when he had an affair.

Rainey’s attorney, then-state Democratic Party Chairman Dick Harpootlian, did not immediately return a message seeking comment. Haley spokesman Rob Godfrey called the ruling the latest proof the allegations are false.

“Every court and every legislative body that has looked at these bogus claims against Gov. Haley has determined that they are without merit,” Godfrey said. “While even a Supreme Court ruling will likely not stop Gov. Haley’s determined political opponents from continuing to make false charges against her, the people of South Carolina see that for what it is.”