NASHVILLE (AP) — A Tennessee lawsuit urges a judge to deem instant runoff voting legal in the state.

Several prospective Memphis city council candidates and IRV Memphis, Inc. sued state elections coordinator Mark Goins and the Shelby County Election Commission earlier this month.

Memphis voters in 2008 approved city election instant runoff voting. They rejected a Nov. 6 referendum repeal attempt.

The system still hasn't been implemented. It lets voters rank choices, avoiding runoffs when no candidate tops 50 percent.

The Davidson County Chancery Court lawsuit says Shelby elections administrator Linda Phillips in July 2017 announced plans for instant runoff voting in 2019 municipal elections.

That September, Goins wrote that Tennessee law doesn't allow ranked-choice voting.

Phillips called the lawsuit premature, with an administrative petition on the issue still undecided.

Goins' office declined comment, citing pending litigation.