But how much impact does the ruling really have?
Attorney General Sessions memo reverses an opinion from Barack Obama's Attorney General Eric Holder.
Sessions ruled Title VI of the Civil Rights Act does not recognize transgender people as protected under the law. He says Title VI forbids workplace discrimination based on sex but says "sex is ordinarily defined to mean biologically male or female."
Attorney Abby Jensen of the Southern Arizona Gender Alliance says, "It's going to confuse a lot of people. It's going to empower people to continue to single out and discriminate and harass trans people by saying, oh well, even the Federal Government says you're not protected."
But a lot of times the last word on what a law is and how it's applied does not come down in some memo from the Justice Department. It's decided in places like Federal Court, where judges take on cases, interpret the law and come up with precedents that really decide how the law's applied in daily life.
Abby Jensen expects that case law to continue to protect trans people from workplace discrimination.
But she says securing protection could require filing a lawsuit or a formal complaint with the Federal Equal Employment Opportunity Commission.
"The only thing that's going to change the EEOC's position is if President Trump replaces commissioners who have a different view of Title VII."
Opinions from KGUN's Facebook page include: "Everyone should be protected...How is this even a question?"
"I don't agree with the lifestyle but everyone needs protecting".
"I can't believe people want to spend their time with those that don't accept them."
Attorney Abby Jensen says trans people should know they can still fight for and secure workplace protections and that Tucson and many other Arizona cities has their own laws against discrimination.