A federal judge took no action Thursday on a request by three University of Texas at Austin professors to temporarily block Texas' campus carry law, saying he won't give his initial ruling until at least next week.

But the case against gained a new wrinkle at a hearing Thursday, with the professors' lawyers now adding a claim that UT-Austin's gun policies are too vague to be enforced.

It remains to be seen whether the challenge will go anywhere. Lawyers on the professors' side admitted in court that their claims wade into uncharted legal waters.

"It goes without saying that this is an interesting case," said U.S. District Judge Lee Yeakel. "Both sides, I thought, did an exceptional job."

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The professors' original argument was that the campus carry law, which allows concealed handgun license holders to take their weapons into classrooms and other public university buildings across the state, violates their First Amendment right to academic freedom. The law went into effect on Monday.

If professors are worried that a student has a gun, the professor might not feel safe teaching controversial issues, they claimed.

But lawyers for the state rejected that idea, saying it isn't based on any empirical evidence. The professors haven't proven that their fear is reasonable, the state's attorney's said.

The law "doesn't prohibit the professors from discussing their views in class," said Anne Marie Mackin, an attorney for UT-Austin.

But during that debate lawyers became confused on what the exact UT-Austin guns policy is. The state law, which went into effect Monday, orders public universities to allow guns. But it doesn't specifically mention professors' role. And lawyers on both sides couldn't point to written UT-Austin policies that describe what would happen to a professor if he or she chooses to ban guns anyway.

Still, the state's lawyers stressed that public university professors are required to uphold state law and that the law prohibits schools from banning guns in classrooms.

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The judge said he wanted to hear more about that argument and asked attorneys on both sides to submit filings detailing their positions. Those are due Monday, and rebuttals can be filed until Wednesday.

Right now, the judge is only considering a preliminary injunction. His decision would only be temporary until a full trial could be held. He will likely rule soon after the filings are submitted.

The lawyers for the professors urged the judge to block the law before classes start for the fall semester on Aug. 24.

"What we are asking for is a time out so that we can take enough time for a full-blown trial in these issues," said attorney R. James George Sr. "Don't risk something tragic happening because we don't want to wait 60 days to have a trial."

Disclosure: The University of Texas at Austin has been a financial supporter of The Texas Tribune. A complete list of Tribune donors and sponsors can be viewed here

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