In roughly two hours of arguments Tuesday, the U.S. Supreme Court struggled with whether a federal law against workplace discrimination protects gay, lesbian and transgender employees and whether the justices or Congress should answer that question.

The justices appeared divided on those issues, but mainly on the text of Title VII of the Civil Rights Act of 1964. The law bars employers from discriminating against workers “because of … sex” and the justices must decide whether that language encompasses sexual orientation and gender identity discrimination.