ATLANTA — The Georgia Supreme Court Tuesday dismissed a lawsuit contesting state Rep. Shea Roberts’ election victory last November.

In a unanimous ruling, the justices upheld a lower court’s decision rejecting a challenge to election results showing Roberts, D-Atlanta, defeated incumbent Rep. Deborah Silcox, R-Sandy Springs, by 377 votes in Fulton County’s House District 52.

After the election results were certified, Sandy Springs resident Warren Schmitz filed a petition in Fulton County Superior Court claiming a variety of irregularities.

The trial court dismissed Schmitz’s challenge last April, determining that he failed to properly serve Roberts with notice of the lawsuit.

Schmitz appealed, arguing the trial court lacked authority to dismiss the case. But the high court disagreed.

“[W]e have long held that it is the responsibility of the person bringing an election contest to ensure that the proceedings move in an expeditious fashion, including by ensuring that all defendants and other interested individuals are given proper notice of the election contest,” Justice Charlie Bethel wrote in Tuesday’s opinion.

Bethel went on to explain that Roberts filed several motions last March stating she had never been properly served with notice of the lawsuit. One day later, the trial court ordered that she be served.

Then a few days later, during a virtual hearing, the trial court noted that it did not see any attempt to have Roberts served in the case.

“Schmitz did not exercise diligence in seeing that she was served despite receiving notice of defects in service at least as early as the date of Robert’s intervention in the case and the filing of … a motion to dismiss raising the issue of insufficient service,” Bethel wrote.

Roberts defeated Silcox 17,069 to 16,692, according to the certified results.