After a tumultuous summer break, during which an impeachment inquiry was officially launched against the President, the US Supreme Court sat for a new session. “Equal Justice Under Law,” reads the motto of the court, emblazoned across the facade in Washington, DC. On the second day of this session, Tuesday 8 October, the court heard two arguments regarding key cases for LGBT+ rights in America—perhaps the most important ruling since the US legalised same-sex marriage in 2015.

The first argument, which combined the cases of Bostock v. Clayton County and Altitude Express v. Zarda, examined whether or not an employee could be fired because of their sexuality. Donald Zarda, a skydiving instructor from New York City (who died in 2014 but is represented by his family), and Gerald Bostock, who worked in child welfare services in Georgia, both claim to have been fired because of their sexual orientation. The court also heard the case of Harris Funeral Homes v. the Equal Employment Opportunity Commission (EEOC), in which Aimee Stephens says she was fired by the Michigan-based funeral home for coming out as transgender.

The law in question is the Civil Rights Act of 1964, a landmark piece of civil rights legislation that “outlaws discrimination based on race, color, religion, sex, or national origin.” It was proposed by President Kennedy in 1963 but was initially opposed in the Senate. It wasn’t until after JFK’s assassination that it was passed through Congress and signed into law by President Johnson in July of 1964. It was one of JFK’s lasting legacies: “No memorial oration or eulogy could more eloquently honour President Kennedy’s memory than the earliest possible passage of the civil rights bill for which he fought so long,” Johnson appealed to Congress. Since then, the Act has been crucial in deciding various key cases of outright and institutionalised racism and sexism. But what about homophobia and transphobia?

All three cases have been through the various federal appeals courts, most of which have interpreted the law to exclude discrimination against LGBT+ people. However, two courts in New York City and Chicago recently ruled the other way. Conservative critics often frame these debates as sexuality and gender identity—decreed to be ‘a choice’—against religious freedoms, with discrimination based on religion protected by law.

The crux of these cases before the Supreme Court is to what extent, if any, does this law apply to matters of sexuality or gender identity. It all rests on the word ‘sex’, with all its sticky associations and divergent meanings. The courts are not there to make laws, but merely to interpret existing law. Any amendments or alterations to the law, such as the addition of sexuality as a basis for discrimination, must be passed by the legislative branch, i.e. Congress.

The attorneys involved thereby had to argue on the basis of sex. Pamela Karlan argued in the first case that “When an employer fires a male employee for dating men but does not fire female employees who date men, he violates Title VII. The employer has discriminated against the man because he treats that man worse than women who want to do the same thing.”

Meanwhile, David Cole argued on behalf of Aimee Stephens, calling for a more modern understanding of the word ‘sex’, without complete revision, claiming that “none of these arguments ask this Court to redefine or update sex. They assume, arguendo, that sex means at a minimum sex assigned at birth based on visible anatomy or biological sex.”

Justice Sonia Sotomayor, one of the liberal judges on the bench, asked “at what point” a court could “continue to allow individual discrimination”. She continued, “We can’t deny that homosexuals are being fired just for who they are.”

Twenty-one states have passed laws that offer LGBT+ employees the necessary protections, but the Court’s eventual opinion will have huge implications for those who live in the other twenty-nine. Human Rights Council press secretary Charlotte Clymer told the BBC, “It’s not about religious freedom, it’s about pushing LGBT people out of the public square.” An affirmative ruling would immediately provide a precedent for necessary and widespread protections, whereas a verdict that fails to uphold the decision of the Chicago and New York courts might be seen to legitimise workplace discrimination, or worse.

Last week, Judy and Dennis Shepard, the parents of Matthew Shepard, who was beaten to death in 1998 in one of the most horrific homophobic attacks in recent history, harshly criticised the Trump administration’s stance on these issues. In a letter read aloud at a Justice Department ceremony marking the 10th anniversary of the law named in part for their son, they singled out Attorney General William Barr—who was absent at the event—in particular for failing to adequately protect transgender people in America.

“If you believe that employers should have the right to terminate transgender employees, just because they are transgender, then you believe they are lesser than and not worthy of protection,” they wrote. “Such blatant discrimination encourages bullying, vandalism and other acts of violence, encouraging close-minded people to push harder against those they consider ‘different’ because they don’t fit their preconceived notions of ‘same’,” they added. “Our son, Matt, was the result of that discrimination and violence when he was beaten brutally and left to die.” Many more are treated the same way, whether it is through emotional or physical abuse. Now, the decision to put an end to this lies in the Supreme Court’s hands.