A federal judge has dismissed a longshot lawsuit filed by three University of Texas at Austin professors seeking to overturn the state's 2015 campus carry law, which allows people to carry concealed handguns inside most public university buildings.

District Judge Lee Yeakel wrote in his decision that the professors — Jennifer Lynn Glass, Lisa Moore and Mia Carter — couldn't present any "concrete evidence to substantiate their fears" that campus carry would have a chilling effect on free speech.

The professors claimed, among other arguments, that the law violated their First Amendment rights since the possibility of a gun being in their classrooms might make them hesitant to discuss controversial issues. In dismissing the suit, Yeakel said the professors didn't have standing to sue.

But Renea Hicks, the attorney representing the three UT professors, said the specifics of the ruling leave the case's future uncertain. While Yeakel threw out the case entirely, he only addressed the question of a First Amendment violation and not the plaintiffs' other legal arguments.

"We had other claims in the lawsuit beyond that — a Second Amendment claim, an equal protection claim. The order accompanying his dismissal doesn't seem to address those issues," Hicks said in an interview Friday. "So there's a bit of confusion on our part."

Hicks, who had not yet conferred with his clients when reached Friday, said he is not sure what course of action he and the plaintiffs will take. They have 28 days from July 6 to ask Yeakel for clarification and 30 days to file an appeal to the U.S. 5th Circuit Court of Appeals.

The ruling was issued late Thursday, exactly one year after the original lawsuit was filed. On Friday, Texas Attorney General Ken Paxton, whose office defended the state in the case, praised the decision.

"The court’s ruling today is the correct outcome," Paxton said. "The fact that a small group of professors dislike a law and speculate about a ‘chilling effect’ is hardly a valid basis to set the law aside."

Campus carry became law in 2015, but didn't go into effect until Aug. 1, 2016. It stirred up widespread opposition among faculty and many students — especially on the UT-Austin campus. But so far, there have been no major incidents, and protests on campus have all but disappeared.

Emma Platoff contributed to this report.

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