Civil District Court Judge Kern Reese “abused” his discretion when he denied a request to suspend his contempt of court ruling against Mayor Mitch Landrieu while the mayor’s attorneys appealed that decision in an effort to keep him from being placed under house arrest, the state Supreme Court said Monday.

The high court instructed Reese to grant the “suspensive appeal” sought by Landrieu’s attorneys, which puts the threat of house arrest on hold while appeals courts look at the issue.

Reese, who is overseeing a decades-old case over $142 million in back pay and interest that the city owes to firefighters, had given Landrieu a deadline of Friday to settle the issue or else be confined to his home on weekends.

The ruling Monday came as the Supreme Court officially accepted the city’s appeal, a move widely expected after the justices issued a last-minute stay on Friday that kept Landrieu from being placed under house arrest.

Even after that ruling came down just before 5 p.m. Friday, Reese ruled against the city’s motion for a suspensive appeal.

The Landrieu administration and the firefighters have been fighting over the case for years, with firefighters demanding back pay they should have received from state-mandated raises that were not provided to them for many years. The city has argued it does not have the money to pay those claims.

The two sides have been in mediation for months trying to negotiate a plan and a timeline for paying the firefighters the money, though the two administration plans that have come out of that effort were rejected by the firefighters.

Reese’s contempt of court judgment and threat of house arrest for Landrieu came after firefighters rejected the second of those plans.

City officials said Friday that the ball is in the firefighters’ court and it is up to them to come up with a counteroffer.

Follow Jeff Adelson on Twitter, @jadelson.