President Trump stirred controversy Monday night by signing an executive order that could bar transgender individuals from serving in the military. The order claims that transgender service members fail to meet the strict demands of military life, though it doesn’t provide evidence to back this up.

The White House’s statement avoided using the word “transgender” but argued that identifying as a gender different from one’s birth sex could conflict with a soldier’s “honorable, truthful, and disciplined lifestyle.” This order directs the Defense Department to create rules preventing transgender individuals from enlisting or continuing their service.

Critics were quick to respond. On Tuesday, advocacy groups filed a lawsuit challenging the ban, calling it a violation of constitutional rights. Shannon Minter, a legal expert involved in the case, described the order as “the nuclear option,” emphasizing that it unfairly targets qualified service members who meet the same standards as everyone else.

This isn’t the first time Trump has attempted such a ban. Similar efforts in the past faced legal battles, and this latest move is likely to reignite the debate over transgender rights in the military.

As the legal fight unfolds, the order raises significant questions about equality and fairness in military service. It remains to be seen how the courts will respond, but one thing is clear: this issue is far from settled.