WASHINGTON – The Supreme Court made it easier yesterday for workers to show they suffered retaliation after accusing employers of discrimination.

By a 9-0 vote, the justices said that Sheila White, a railroad forklift operator, was improperly punished when her employer suspended her for 37 days over a Christmas holiday and reassigned her to more physically demanding duties as a yard worker. She had accused a supervisor of sexual harassment.

The ruling significantly eases the legal standard for showing retaliation and could lead to more litigation against companies.

Under the court’s new standard, the justices defined retaliation as any action taken by an employer that would intimidate “a reasonable employee” into backing off from a discrimination complaint.

Ms. White was the only woman working in the rail yard for the Burlington Northern Santa Fe Railway in Memphis, Tenn., when she was hired because of her experience operating a forklift.

A company investigation of Ms. White’s sexual harassment allegations led to a foreman’s suspension and enrollment in sensitivity classes. But the railroad simultaneously transferred Ms. White to work as a regular track worker, a more physically demanding job.

The railroad eventually cleared Ms. White of insubordination charges that also were lodged against her.

A jury rejected the sex discrimination charge but found in her favor on the retaliation claim, awarding her $43,000.

Justice Breyer wrote that even though Ms. White did receive back pay, she and her family had to live 37 days without any income, not knowing when or if she would return to work.

“Many reasonable employees would find a month without a paycheck to be a serious hardship,” Justice Breyer wrote, adding that “an indefinite suspension without pay could well act as a deterrent, even if the suspended employee eventually received back pay.”

Justice Breyer said the court’s ruling doesn’t immunize employees who complain of discrimination from “those petty slights or minor annoyances that often take place at work and that all employees experience.”

He said it will be up to trial courts to determine on a case-by-case basis whether reasonable employees would have been intimidated by actions taken by employers.

“Context matters,” Justice Breyer wrote.

A schedule change may not bother many workers, he said, but it may matter greatly to a young mother with small children. Or, Justice Breyer said, a supervisor’s failure to invite a worker to lunch might seem trivial unless the luncheon was a weekly training session crucial to the employee’s advancement.