Some of the country's best-known brands filed a brief with the court Wednesday, including American Airlines, Apple Computers, CBS and Starbucks Coffee, as well as the Tampa Bay Rays baseball team and Miami Heat basketball team.
They are urging the court to take up the case of a female security guard at a Georgia hospital. Jameka Evans quit her job after she was harassed and persecuted because she is gay and preferred to wear a man's uniform.
While many U.S. states include protections for gays in laws prohibiting discrimination on the basis of sex, there is no federal law.
A federal appeals court threw out Evans' suit against the hospital in March, upholding lower court rulings that the Civil Rights Act of 1964 bars discrimination on the basis of gender, but not sexual orientation.
The Trump administration believes the law should stand as it is. But the businesses wrote in their petition that everyone benefits when everyone is protected.
'Businesses' first-hand experiences, supported by extensive social-science research, confirm the significant costs for employers and employees when sexual orientation discrimination is not forbidden by a uniform law, even where other policies exist against such discrimination,' the brief says.
The court is expected to decide by the end of the year whether it will take Evans' case.