SAN FRANCISCO — A federal judge in San Francisco on Thursday found that the mass firings of probationary employees were likely unlawful, granting some temporary relief to a coalition of labor unions and organizations that have sued to stop the Trump administration’s massive trimming of the federal workforce.

The ruling puts one of the most comprehensive pauses so far on the attempts of President Donald Trump’s administration to carry out mass firings across federal agencies.

The case specifically grappled with the involvement and oversight of the Office of Personnel Management, led by acting director Charles Ezell, in directing agencies to cut back their workforces beginning with shorter-term, or probationary, employees.

At a hearing on Thursday afternoon, US District Judge William Alsup ordered the Office of Personnel Management to inform certain federal agencies that it had no authority to order the firings of probationary employees, including the Department of Defense.

The order may have the immediate impact of putting on hold mass firings of federal probationary workers.

“OPM does not have any authority whatsoever, under any statute in the history of the universe,” to hire or fire any employees but its own, Alsup said.

Alsup handed down the order on a temporary restraining order sought by labor unions and nonprofits in a lawsuit filed by the coalition filed last week. He had sought more clarity before the hearing on the extent of the involvement of OPM in directing agencies to cut staff.

A sworn statement from Ezell filed in court told the judge OPM wasn’t conducting a “mass termination program,” and “did not direct agencies to terminate probationary employees, based on performance or misconduct.” Ezell said the individual agencies were “responsible” for taking their own action to cut jobs and review workers’ performance.

Ezell did, however, say he “issued guidance” to federal agencies on Trump’s first day in office, and again this month, that probationary employees weren’t finalized hires in the government and that agencies should “manage staffing levels,” according to the court filing.

Thousands of probationary employees have lost their jobs from several agencies, including the IRS, and the Trump administration has pledged to fire thousands more. The probationary workers have fewer protections from being fired than those who have served for longer time periods in their positions.

The complaint filed by five labor unions and five nonprofit organizations is among multiple lawsuits pushing back on the administration’s efforts to vastly shrink the federal workforce, which President Donald Trump has called bloated and sloppy.

The plaintiffs say OPM had no authority to terminate the jobs of probationary workers who generally have less than a year on the job. They also say the firings were predicated on a lie of poor performance by the workers.

Lawyers for the government say OPM did not direct the firings, but asked agencies to review and determine whether employees on probation were fit for continued employment. They also say that probationary employees are not guaranteed employment and that only the highest performing and mission-critical employees should be hired.

There are an estimated 200,000 probationary workers – generally employees who have less than a year on the job – across federal agencies. About 15,000 are employed in California, providing services ranging from fire prevention to veterans’ care, the complaint says.

The plaintiffs celebrated the order Thursday but noted it was just a first step in their legal fight over the mass firings.

“This ruling by Judge Alsup is an important initial victory for patriotic Americans across this country who were illegally fired from their jobs by an agency that had no authority to do so,” Everett Kelley, national president of the American Federation of Government Employees, said in a statement. “OPM’s direction to agencies to engage in the indiscriminate firing of federal probationary employees is illegal, plain and simple, and our union will keep fighting until we put a stop to these demoralizing and damaging attacks on our civil service once and for all.”

Unions have recently struck out with two other federal judges in similar lawsuits attempting to stop the Trump administration’s goal of vastly reducing the federal workforce.

The case out of San Francisco so far has gone differently because of Ezell’s apparent focus on the alleged direct involvement of OPM in the federal workforce reductions. In other cases, judges have initially found they may not have authority to step in because other avenues outside the federal courts are available to fired workers.

The MSPB, however, which is one place fired federal workers can go seeking to challenge their removals, ordered the temporary reinstatement of six probationary workers who lost their jobs under Trump’s cutbacks.

The decision earlier this week found that those firings were likely unlawful. Lawyers representing the workers’ interests have vowed to try to expand the board’s finding to apply to thousands more probationary workers.

Alsup said on Thursday the Trump administration should turn over evidence related to the case next week, and a hearing is scheduled for mid-March in the fast-moving court case.

Alsup, who was appointed by President Bill Clinton, a Democrat, has presided over many high-profile cases and is known for his blunt talk. He oversaw the criminal probation of Pacific Gas & Electric and has called the nation’s largest utility a “continuing menace to California.” — CNN