TRENTON -- The state Supreme Court on Wednesday ruled Atlantic County and Bridgewater Township committed unfair labor practices when they refused to pay employees' step increases after labor contracts with public workers expired.

The state's high court upheld the appellate court in a rebuke to the Public Employment Relations Commission, which had decided local governments don't have make step increases -- raises in pay when workers reach annual milestones in years of service -- during lapses in contracts even though explicit contract language guaranteed it.

Gov. Chris Christie's administration had also denied step increases to tens of thousands of state workers who have no contract. It's not clear whether the ruling will prompt the administration to restore them.

Justice Lee Solomon, writing for the court, said "Here, we need not look beyond the contracts themselves to conclude that the step increases continued beyond the expiration of the contracts."

The expired contracts contained "clear and explicit language" that Atlantic County and Bridgewater should have adhered to the salary grid, the court said unanimously.

One contract said "provisions of this agreement will continue in effect until a successor agreement is negotiated." And another, "all terms and conditions of employment ... shall be continued in full force and effect."

"Accordingly, we find that the salary increment systems remained in effect after the agreements' expiration dates under the basic principles of contract law."

The Fraternal Order of Police Lodge 34 and Policemen's Benevolent Association Local 77 had charged Atlantic County with unfair labor practices, alleging the county violated a four-decades-old "dynamic status quo" doctrine that guides the term between contracts.

Police officers who were not yet at the top of the pay scale were due 5 percent or 6 percent step increases.

The county asserted, and PERC agreed, that the doctrine no longer reflected the economic landscape or the challenges local governments face in complying with state-imposed 2 percent caps on tax levy hikes.

The dynamic status quo doctrine was meant to create a level playing field for negotiations. But attorneys arguing against the automatic step increases said it became a disincentive for unions to quickly settle labor disputes.

The court did not weigh in on the viability of the status quo doctrine, finding the contract language was strong enough grounds for its decision.

Bridgewater followed Atlantic County's example. In that companion case, PERC went so far as to say automatic increases between contracts could no longer be negotiated for.

The Supreme Court said in its opinion that salary step increments are, in fact, a matter for negotiations and arbitration.

"The unilateral modification at issue here directly contradicted the parties' binding written agreement," Solomon wrote.

The unions in question have since settled their contracts and their increments have been paid, said Ira Mintz, an attorney for the police unions.

The Christie administration relied on the Atlantic County and Bridgewater PERC decisions in freezing salaries for tens of thousands of state workers.

Hetty Rosenstein, state director of the Communications Workers of America, the largest state workers union, said members haven't received step increases since July 1, 2015.

"It's now a question of whether the administration will restore our increment based on Atlantic County and Bridgewater," Rosenstein said, adding that if they don't, "We believe we have the legal tools now to get our increments paid."

"It's good news. It's a good decision. But like everything else with this administration, nothing is easy," she said.

Samantha Marcus may be reached at smarcus@njadvancemedia.com. Follow her on Twitter @samanthamarcus. Find NJ.com Politics on Facebook.