WASHINGTON, April 23 (Reuters) - The U.S. Supreme Court

on Tuesday steps into the contentious unionization drive at

Starbucks ( SBUX ) as the coffee chain challenges a judicial

order requiring it to rehire seven employees at a Tennessee cafe

who were fired as they pursued efforts to organize.

The justices are set to hear arguments in the company's

appeal of a lower court's approval of an injunction sought by

the U.S. National Labor Relations Board ordering the

reinstatement of the workers. It is a case that could make it

harder to bring a quick halt to labor practices challenged as

unfair under federal law while the NLRB resolves complaints.

The case centers on the legal standard that federal courts

must use to issue a preliminary injunction requested by the NLRB

under the a federal law called the National Labor Relations Act.

Such orders are intended as an interim tool to halt unfair labor

practices while a case is proceeding before the board.

Under section 10(j) of the labor law, a court may grant an

injunction if it is deemed "just and proper." Starbucks ( SBUX ) contends

that if the lower courts had applied stricter criteria, similar

to the standard used by some other courts and in non-labor legal

disputes, the case would have come out differently.

About 400 Starbucks ( SBUX ) locations in the United States have

unionized, involving more than 10,000 employees. Both sides at

times have accused the other of unlawful or improper conduct.

Hundreds of complaints have been filed with the NLRB

accusing Starbucks ( SBUX ) of unlawful labor practices such as firing

union supporters, spying on workers and closing stores during

labor campaigns. Starbucks ( SBUX ) has denied wrongdoing and said it

respects the right of workers to choose whether to unionize.

In a break from the acrimony, both sides in February said

they had agreed to create a "framework" to guide organizing and

collective bargaining and potentially settle scores of pending

legal disputes.

The case began in 2022, when the workers at the Poplar

Avenue store in Memphis became among the first to unionize.

Early in their efforts, they allowed a television news crew into

the Starbucks ( SBUX ) cafe after hours to talk about the union campaign.

Seven workers present that evening were fired, including several

who belonged to the union organizing committee.

Despite the dismissals, employees there later voted to join

Workers United.

The union filed unfair labor charges with the NLRB over the

firings and other discipline by managers. The NLRB sought an

injunction, alleging that Starbucks ( SBUX ) unlawfully fired the workers

for supporting the union drive and to send a message to other

workers.

U.S. District Judge Sheryl Lipman granted the injunction in

2022, reinstating the workers in order to address the "chilling

effect" of the dismissals on the unionization effort while the

NLRB resolves the case. The Cincinnati, Ohio-based 6th U.S.

Circuit Court of Appeals upheld the injunction in 2023.

The 6th Circuit rejected the company's argument that Lipman

should have used a stringent four-factor test to weigh the bid

for an injunction, as courts typically do in non-labor disputes.

This test includes an assessment of whether the side seeking

relief would suffer irreparable harm and is likely to succeed on

the merits of the case.

The Supreme Court's ruling is expected by the end of June.