WASHINGTON – The Supreme Court agreed Monday to decide the next major legal dispute over gay rights: whether the nation's job discrimination laws apply to sexual orientation and gender identity.

The justices will hear three challenges from New York, Michigan and Georgia involving workers who claim they were fired because they were gay or transgender:

A New York skydiving instructor, Donald Zarda, said he was fired because he was gay. He has died, but his sister and life partner continue to press the case.

A Georgia county government employee, Gerald Bostock, alleged he was fired from his job as a child welfare services coordinator because he is gay.

A Michigan transgender woman, Aimee Stephens, said she was fired from the funeral home where she worked for six years as Anthony Stephens because of her transition.

All three cases raise the question of job discrimination against gay, lesbian and transgender workers. A decision in the challengers' favor would mark an important step in the effort to protect the LGBT community from discrimination in employment, housing and public accommodations, advocates said.

"The decisions in these cases will shape the legal landscape for LGBT people for decades to come," said Shannon Minter, legal director at the National Center for Lesbian Rights. "A Supreme Court decision reversing these established protections would be catastrophic for LGBT people and disruptive for businesses, who would face a patchwork of conflicting state laws."

The justices had considered whether to hear any of the cases since early January – usually an indication they would refuse them, with one or more justices writing a dissent. Instead, they agreed to hear all three cases.

The Justice Department under President Donald Trump supported the companies, contending that federal civil rights laws do not protect workers based on sexual orientation or gender identity.

In the Michigan case, Stephens successfully challenged her firing before the Equal Employment Opportunity Commission and again at the 6th Circuit Court of Appeals, both of which ruled her dismissal violated federal law.

“The court’s decision to take this case is a historic turning point for transgender people across this country," said Mara Keisling, executive director of the National Center for Transgender Equality. "Any decision by the court on this matter could fundamentally alter the lives of people who already struggle to secure fair and equitable employment."

Appeals courts are divided over whether a federal law that bans discrimination on the basis of sex includes sexual orientation. The U.S. Court of Appeals for the 2nd Circuit, based in New York, and the 7th Circuit, based in Chicago, ruled that sex discrimination laws protect gays and lesbians.

The 11th Circuit, based in Atlanta, said they do not. And the 6th Circuit, based in Cincinnati, said transgender people are protected.

The Supreme Court refused in 2017 to enter the fray by considering a Georgia woman's complaint that she was fired from her job because she is a lesbian. It was a setback for gay rights groups that hoped to get the issue to the high court before last summer's retirement of Associate Justice Anthony Kennedy, the court's frequent swing vote and author of several landmark gay rights decisions.

Title VII of the 1964 Civil Rights Act bars discrimination based on sex, race, color, national origin and religion. It does not specifically address sexual orientation or gender identity.

In the 7th Circuit, Judge Diane Wood ruled in 2017 that "it is actually impossible to discriminate on the basis of sexual orientation without discriminating on the basis of sex." In the 11th Circuit, Judge William Pryor said Congress "has not made sexual orientation a protected class."

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