*Editor's note: This story has been updated throughout.

A move by state Sen. Don Huffines, R-Dallas, to put a controversial provision back into open carry legislation threw the Texas Senate into a tense debate Friday that ended only when all sides agreed let the argument rest until later in the day.

The chamber plunged into rare unscripted territory after Huffines offered an amendment to a bill allowing Texans with licenses to carry handguns openly. The measure, approved overwhelmingly when the House passed the open carry bill, would prohibit police officers from stopping someone solely because they are visibly carrying a handgun. It was taken out when the legislation reached the Senate.

An expected routine debate on passing the bill escalated dramatically when an unusual alliance formed between two urban Democrats and conservative Republicans who supported the amendment for different reasons.

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Conservatives, including Huffines, argued that the language was necessary to protect the Fourth Amendment rights of handgun license holders who could be subject to harassment from police officers.

Democrats Rodney Ellis of Houston and Royce West of Dallas threw their support behind Huffines, saying that — while they oppose open carry itself — with the bill all but certain to pass they want protection from racial profiling by police.

A previous version of the open carry measure cleared the state Senate along party lines in March, but the chamber is now working with the House version of the bill. 

Sen. Craig Estes, the Wichita Falls Republican sponsoring the bill in the Senate, said the amendment would create unnecessary confusion for law enforcement — and that he believed existing law already prevented law enforcement from asking people for proof that they have a license without some other suspicion. Estes said he ultimately planned to vote against the amendment, but would accept the will of the chamber.

Several other Republicans, including Robert Nichols of Jacksonville and Joan Huffman of Houston, said they viewed the amendment as back-door effort to repeal handgun licensing requirements altogether.

Huffman said she thought the provision was a “poison pill” for the legislation, echoing Estes in saying it would threaten overall support for the bill. 

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“I want to go on record saying this is a mistake. This is bad for Texas,” she said.

The fiercest opposition to the amendment came from Sen. John Whitmire, the Houston Democrat who chairs the Criminal Justice Committee. 

Whitmire called the measure “a game-changer” that would endanger the lives of police officers.

He repeatedly questioned Huffines about whether he had thought through the consequences for law enforcement — urging the Republican to pull the amendment down to allow time for further discussion.

“What if you are wrong, Senator Huffines? Do you ever doubt yourself that police officers know more about public safety than you do?” Whitmire asked his colleague. “Do you ever worry that your amendment is going to cost police officers their lives?”

Huffines responded that he had “confidence that they will exercise great discretion” when presented with dangerous situations.

After more than 90 minutes of debate on that amendment alone, Estes opted to temporarily pull the bill from consideration. The chamber will take the bill up again at 6 p.m. today.

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