The Supreme Court grappled Tuesday with whether and how far to get in front of Congress in determining whether a 55-year-old civil rights law covers discrimination on sexual orientation and gender identity.

Justice Stephen Breyer called the role of Congress “the elephant in the room” during arguments on three cases about how to apply Title VII of the Civil Rights Act of 1964 in a country that has changed drastically since its initial passage. The cases hinge on if the court decides whether discrimination “on the basis of sex” includes whether the person is attracted to the same gender or identifies as the opposite of what they were assigned at birth.

[Congressional inaction drives LGBT rights case at Supreme Court]

Members of the court’s conservative wing questioned whether it was their place to read sexual orientation and gender identity into Title VII. At one point, Justice Neil M. Gorsuch described the petitioners’ preferred outcome as “essentially a legislative decision,” and noted the court needs to keep in mind its “judicial role and modesty” when approaching statutory interpretation.

Justice Samuel A. Alito Jr. pushed the petitioners to answer the likely criticism that “if the Court takes this up and interprets this 1964 statute to prohibit discrimination based on sexual orientation, we will be acting exactly like a legislature.”

Breyer, along with Justices Sonia Sotomayor, Ruth Bader Ginsburg and Elena Kagan, noted the law did not initially cover sexual harassment or adherence to traditional gender stereotypes, but that the high court has interpreted the law to include them. Breyer noted that gay, lesbian and transgender Americans were discriminated against at the time, similarly to the groups the civil rights law was originally meant to protect.

“That’s a change that both explains why they didn’t put it in initially and explains why we should, other things being equal, interpret it to include gay people and transgender people now?” Breyer said.

The petitioners in the cases argued that the statute doesn’t require an “update,” but merely recognition that discrimination based on sexual orientation is covered by sex discrimination.

“When you tell two employees who come in, both of whom tell you they married their partner, Bill, last weekend, when you fire the male employee who married Bill and you give the female employee who married Bill a couple of days off so she can celebrate the joyous event, that’s discrimination because of sex,” petitioner counsel Pamela Karlan said.

Grappling with legislative history

Litigants arguing to allow discrimination based on sexual orientation have leaned on the history of the statute, claiming that no one in 1964 considered sex discrimination to include sexual orientation. Additionally, they pointed out that Congress has considered legislation to expand Title VII to include sexual orientation.

In May, the House passed the Equality Act on a 236-173 vote. The measure would prohibit discrimination on the basis of sex, sexual orientation and gender identity. Democrats, including primary sponsor Rep. David Cicilline, D-R.I., have argued the legislation, which the Senate has yet to take up, should be considered separately from Title VII.

Republican lawmakers, though, have said in court papers that Congress has the ability to alter Title VII and “if Congress intended to include sexual orientation and gender identity among the protected classes in Title VII, it could have done so.”

Both Republicans and the Justice Department argued that Congress did not add those protections to Title VII when it overhauled the law in 1991.

DOJ and case respondents argued that Congress has differentiated between sex, sexual orientation and gender identity in other statutes, indicating the legislature regards them as different traits. Additionally, more than 20 states have enacted their own protections for sexual orientation, respondents said, suggesting they want the statutes to go beyond what the federal government provide.

The split among circuits has not come about until recently, when the Second and Seventh Circuits ruled the law included sexual orientation discrimination.

During arguments, U.S. Solicitor General Noel Francisco said that ruling ahead of Congress would “deprive the people of the ability to struggle with these issues democratically.” He argued that a court ruling also would skip the balancing test typically struck by legislatures between discrimination and religious freedom.

“If you resolve this in this way, and I hate to use this language, is a complete victory to one side of the fight and nothing to the other,” Francisco said.

Kagan pushed back against Francisco, saying “those arguments are not ones we typically would accept,” as the Supreme Court has moved away from reading the tea leaves of legislative intent in favor of textual interpretation.

“The text of the statute appears to be pretty firmly in Karlan’s corner,” Kagan said.