The Senate witnessed an unusual and intense dispute among Democrats on Tuesday when Sen. Cory Booker opposed the unanimous approval of a bipartisan set of police funding proposals.

The unexpected confrontation revolved around seven initiatives, previously endorsed by the Senate Judiciary Committee, aimed at enhancing resources and safety measures for first responders and police officers.

“I’m exhausted by the president of the United States breaching the Constitution, undermining our traditions, and how does the Democratic Party respond? By complying? Permitting? Settling for less? I demand justice,” declared Booker, D-N.J., in the Senate chamber.

“It’s time for Democrats have a backbone. It’s time for us to fight. It’s time for us to draw lines,” he added.

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Booker’s stance on the package was countered by Sen. Catherine Cortez Masto, D-Nev., a law enforcement supporter in the Senate who was advocating for the legislative package on the floor.

Booker sought to adjust the funding proposals, contending that the public safety grants would favor law enforcement agencies in Trump-preferred states while disadvantaging others. He stated that his amendment offered a crucial provision to protect the grants from being politically biased.

“I propose we reject this and demand, in a united manner, an end to this constitutionally unfair allocation of resources that we endorse,” Booker stated regarding the legislative package.

Cortez Masto rejected Booker’s amendment, calling it a “poison pill” since the legislation had already passed through a committee of which Booker is a member.

“I agree, withholding funding for law enforcement anywhere in the country, across the country, is just not acceptable,” Cortez Masto said. “But I also agree that two wrongs don’t make a right.”

Booker said the contention that his amendment was a “poison pill” was “ridiculous.” He then blocked the package of bills, which all of the other Democrats in his caucus had agreed to pass unanimously with Republicans.

Sen. Amy Klobuchar, D-Minn., said Democrats have engaged in “a long dispute over this type of funding” that predated the Trump administration. She appeared to choke back emotion in defense of the legislation.

“I completely agree with Sen. Booker about what this administration is doing. But you can’t just pick out a few bills that came out of a committee and say, ‘I’m going to stop those,’ and then allow for other bills that fund other parts of your budget in your state,” Klobuchar said.

Cortez Masto and Klobuchar had worked alongside Republicans on the bills, which focused on providing additional protections, training and tools for officers and their families.

Booker responded by sharply rejecting what he framed as assaults on his “integrity” and “motives.”

“I am standing for my police officers. I’m standing for the Constitution, and I’m standing for what’s right. And dear God, if you want to come at me that way, you’re gonna have to pick it up with me, because there’s too much on the line right now in America,” he said.

“When are we going to stand together for principles that I just heard that were agreed with?” he added.

Booker also took aim at the Democratic Party as a whole, saying, “This, to me, is the problem with Democrats in America right now is we’re willing to be complicit to Donald Trump.”

“We are standing at a moment where our president is eviscerating the Constitution of the United States of America, and we’re willing to go along with that today. No, no, not on my watch,” he added.

Cortez Masto later moved to unanimously pass just two of the seven bills, which were approved after Booker did not object. Those measures would include certain retired law enforcement officers in a death benefits program and establish standards for trauma kits.

Booker said he supported them “because they will apply to every officer in the United States of America. That’s the way this body should work, and I have no objection whatsoever.”

The public sparring provided an extraordinary glimpse into an internal debate among congressional Democrats as they struggle to navigate the need to legislate in the face of a Trump administration that has at times put up roadblocks to congressional directives.

Cortez Masto, who was advocating for the passage of the package Booker objected to, also voted with Republicans to pass a short-term government funding package in March, a move seen as pragmatic by some but viewed as capitulation by many on the left looking for a fight in Trump’s second term.

In comments off the floor, Booker told reporters, “There’s a lot of us in this caucus that want to f—–g fight, and what’s bothering me right now is we don’t see enough fight in this caucus.”

Booker has emerged as a key Democratic voice in opposition to the Trump administration. He set the record for the longest speech in Senate history this year in remarks that said the Trump administration presented a “grave and urgent” threat to the country.

Cortez Masto told NBC News after the floor debate that she “was disappointed” by some of Booker’s rhetoric that Democrats are “not doing enough to take on Donald Trump.”

“I come from a swing state and have to beat back opponents to win my state and take on Donald Trump,” Cortez Masto said. “So it really is to me about how we work together to keep our communities safe and pass bipartisan, unanimous legislation that really came out of this committee, and that’s where our focus should be.”