The Texas AFL-CIO wants to intervene as a defendant in thechallenge over the U.S. Labor Department’s overtime-pay rule, fearing that federalagencies under Donald Trump will not adequately defend the Obamaadministration regulations.

Related: 21 states sue to block overtimerule

A federal trial judge in November blocked the rule, which wouldhave expanded the scope of eligibility for overtime pay to millionsmore workers. The U.S. Court of Appeals for the Fifth Circuitgranted a request from the Justice Department, litigating the casefor labor regulators, to expedite the government’sappeal.

But the litigation in the appeals court will spill into Trump’sadministration, giving his Justice and Labor departments a chanceto revise their position in the litigation. That worries the TexasAFL-CIO.

“We’re not saying that the Department of Labor and theDepartment of Justice haven’t forcefully defended the regulations[so far], but as for whether that will continue in the future,we’re starting to have serious concerns,” Yona Rozen, an assistantgeneral counsel at the AFL-CIO, said in an interview Monday. Rozenis representing the Texas branch in the litigation in front of U.S.District Judge Amos Mazzant III in the Eastern District ofTexas.

Related: Wage and hour suits have beenrising

The AFL-CIO branch’s rare motion, filed Dec. 9, marks thelatest chapter in a long fight over the rules, which laborregulators contend will provide time-and-a-half overtime pay to anadditional 4 million workers.

The plaintiffs in the case, including 21 states, won apreliminary injunction last month. The challengers in theconsolidated litigation—including the states and business groupssuch as the U.S. Chamber of Commerce—contend the rules violatedstates’ rights and the Administrative Procedure Act.

In order to intervene in the case, the Texas AFL-CIO must showit has sufficient interest in the issues and that its positionwon’t be represented adequately by the current nameddefendants.

The plaintiffs oppose the Texas AFL-CIO’s request to intervene.The Justice Department on Monday said it takes no position on theTexas labor group's request.

The motion filed by the Texas AFL-CIO, a federation of 650 localTexas unions, anticipates that Trump’s Labor Department will notsupport the rule. Andrew Puzder, the fast-food company chiefexecutive who is Trump’s pick for Labor secretary, has opposed the Obamaadministration’s push to boost worker-pay.

“With the recent presidential election, and particularly as moreinformation becomes available regarding the incomingadministration’s plans, policy and appointments, the Texas AFL-CIOhas grave concerns as to whether its interests in the final rulewill be represented by the DOL,” the labor group wrote in its courtpapers.

Attorneys for the AFL-CIO said that losing the overtime ruleswould cause workers to suffer a “downward pressure” on salaries andbenefits created by following the existing overtime rule standards,which have not been updated since 2004.

The Office of Texas Attorney General Ken Paxton declined tocomment on the AFL-CIO motion, citing the ongoing litigation.

A spokesperson for the U.S. Chamber said in an email: “Webelieve Judge Mazzant's opinion was correct and we look forward todefending it on any appeal.”