A federal appeals court in Washington, D.C., on Monday denied the Justice Department's efforts to lift a temporary halt on four federal executions.

The department had appealed a trial judge's ruling last month that ordered a stay of the executions while a separate legal challenge to the Trump administration's new lethal injection protocol plays out.

The longest running of the four lawsuits was filed 16 years ago, and the cases went dormant during the Obama administration amid a shortage of lethal injection drugs.

The first of the four executions was set for Dec. 9. The only other federal death row prisoner with an upcoming execution received a stay from another circuit court.

In July, Attorney General William Barr Bill BarrFederal prosecutor speaks out, says Barr 'has brought shame' on Justice Dept. Why a backdoor to encrypted data is detrimental to cybersecurity and data integrity FBI official who worked with Mueller raised doubts about Russia investigation MORE announced that federal executions would resume with the launch of a new lethal injection protocol that utilizes a single drug, pentobarbital, in lieu of the previous three-drug "cocktail" that was becoming increasingly difficult to obtain.