Several years after the Supreme Court expanded legal protections to workers suing their employers for discrimination, U.S. workers are accusing their employers of unlawful retaliation in record numbers.

A record 38,539 retaliation charges were reported in fiscal year 2013 to the Equal Employment Opportunity Commission, the federal agency that enforces antidiscrimination laws in the workplace.

That caps eight years of steady growth in the number of retaliation claims American workers are filing with the agency, which include claims of getting demoted, fired or denied promotions in retaliation for complaining about race, gender or other types of discrimination in the workplace. It marks the fifth consecutive year that retaliation overtook race discrimination as the most commonly reported form of discrimination in the workforce.

Local data reflects a similar trend. Between 2009 and 2013, the number of retaliation charges jumped 16 percent in the District, 52 percent in Maryland and 18 percent in Virginia, according to EEOC statistics. So far this year, the EEOC has reached settlements with three Maryland employers sued over alleged retaliation: a $42,000 settlement against Hagerstown, Md., trucking company Winebrenner Transfer on behalf of a female truck driver who was fired after complaining about being paid less than her male counterparts; a $200,000 settlement against Basta Pasta, on behalf of a manager who was fired after reporting instances of sexual harassment against female employees; and a $22,500 settlement against Annapolis Internal Medicine, on behalf of a receptionist who was fired after complaining about pregnancy discrimination.

A small percentage of charges filed with the EEOC eventually become lawsuits. But the fact that retaliation is being cited more often indicates that people’s attitudes about workplace discrimination may be evolving, some legal experts said.

“It’s employees becoming more aware of their rights and being willing to exercise them,” said Robert Weisberg, regional attorney of the EEOC’s Miami district. “I see often where there’s sexual harassment that in the past might have been tolerated, now is leading to internal complaints of discrimination, and that then sets the stage for retaliation of some sort.”

The rise can also be attributed to two Supreme Court decisions from the last decade that expanded both the pool of people who could sue over such claims, and the types of things they could sue for.

In 2006, in Burlington Northern & Santa Fe Railway Co. v. White, the Supreme Court broadened the type of employer misconduct that the law considers retaliation. In that case, the court found that an employee does not necessarily have to be punished with a clear-cut “adverse” action — such as getting demoted or fired — but that a more nuanced form of punishment, such as receiving less desirable assignments, counts as retaliation under the law.

And in 2011, in Thompson v. North American Stainless, the court expanded who could sue an employer for discrimination, ruling that a man who was fired after his fiance accused their mutual employer of sex discrimination was entitled to sue for retaliation.

Within the federal workforce, complaints of discrimination and retaliation tend to be cyclical, going up during times of fiscal hardship, said Cheri Cannon, an employment attorney at Tully Rinckey who represents federal employees and managers in EEOC matters.

“Right now, the government is shrinking in some sectors, they’re letting people go, they’re not hiring as fast because of the fiscal constraints,” Cannon said. “When that happens, it squeezes the employees and it becomes an issue of, ‘You’re doing something to me, how am I going to protect myself?’ People have to have an explanation for why bad things are happening to them that don’t necessarily have to do with money.”