Why wait for Detroit.

It was widely expected that Democratic presidential nomination rivals Joe Biden and Sen. Cory Booker could tangle at next week’s second round of presidential primary debates in Detroit over the issues of race and criminal justice, when the two candidates stand next to each other center stage.

But the first punches are already being thrown.

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Just a couple of hours after the former vice president on Tuesday morning unveiled a wide-ranging plan to reduce the country’s prison population, reform the nation’s criminal justice system and eliminate racial and income disparities in sentencing, Booker took aim.

“It’s not enough to tell us what you’re going to do for our communities, show us what you’ve done for the last 40 years. You created this system. We’ll dismantle it,” tweeted the senator from New Jersey, who is black.

Booker was referencing Biden’s deep involvement in drafting the 1994 crime bill, which has made criminal justice reform a tricky issue for the current front-runner in the race for the Democratic presidential nomination.

As a senator from Delaware, Biden helped craft the 1994 crime bill that was signed into law by then-President Bill Clinton. Biden has long highlighted his role in helping write the law, which at the time was the largest anti-crime bill in the nation’s history. The measure provided for thousands of new police officers, millions of dollars to fund prevention programs, and billions of dollars to build new prisons.

But the law’s long been criticized by Democrats who blame the measure for spiking incarcerations, particularly among minorities, due to a mandatory life sentence policy for repeat offenders.

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Biden’s new criminal justice plan – in fact – would reverse the stricter sentences terms for crack versus powder cocaine that were implemented by the 1994 law.

Last month on the campaign trail, Biden emphasized that "only one provision in there that had to do with mandatory sentences that I opposed. And that was a thing called the 'three strikes and you're out,' which I thought was a mistake. But it had a lot of the good things in the bill."

But facing jabs from numerous rivals over the law, Biden has repeatedly defended many other aspects of the measure.

Biden, who remains the front-runner in the Democratic nomination race in part thanks to his strong support from black voters, credited the law’s gun control provisions – including the assault weapons ban – which he said helped him “beat the NRA.”

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In late May, Booker slammed the bill, saying it “was awful.”

And in an interview with the Huffington Post, he also emphasized that “we should all agree with the force of conviction: That bill was a mistake…Good people signed on to that bill. People make mistakes. But let's hold them to that. That crime bill was shameful, what it did to black and brown communities like mine.”

The Booker campaign on Tuesday told Fox News that “the tweet stands for itself” and described it as a “pretty direct response” to Biden’s new criminal justice proposal.

But a few hours later, to hammer home the point, the candidate released a statement saying "Biden had more than 40 years to get this right. The proud architect of a failed system is not the right person to fix it."

Booker argued that Biden’s “plan falls short of the transformative change our broken criminal justice system needs” by not legalizing marijuana, overhauling policing practices, forcefully using the presdiential clemency power, or reinvesting in communities hard hit by mass incarcerations.



The former vice president’s campaign highlighted that the new proposal, officially titled the ‘Biden Plan for Strengthening America’s Commitment to Justice,’ would prioritize reform of the juvenile justice system -- using $1 billion per year “to make sure we give more children a second chance to live up to their potential.”

Senior Biden campaign officials told Fox News on Tuesday that the sweeping plan would be paid for using costs saved from reducing mass incarcerations.

Biden’s expected to spotlight his plan this week while addressing an NAACP presidential candidate’s forum Wednesday in Detroit, as well as the next day in Indianapolis when he speaks at the National Urban League’s annual conference. Booker will also be speaking at both events.

Fox News reached out the Biden campaign for any response to Booker’s tweet, but they declined to respond to Booker’s jab.

This isn't the first time the two candidates have thrown verbal punches at each other.

Last month Booker called on Biden to apologize after controversial comments from the former vice president spotlighting his ability to find common ground in the Senate four decades ago with segregationist senators with whom he vehemently disagreed.

Biden later said Booker owed him an apology.

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Sen. Kamala Harris of California will be standing on the other side of the former vice president at next week’s showdown. She’s also criticized Biden over the 1994 crime bill, and sparred dramatically with him at last month's debate over his stance on busing.

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Booker, trailing in the polls, could be setting the stage to similarly confront the former vice president in Detroit.

A week ahead of the debates, though, Detroit Mayor Mike Duggan endorsed Biden.

The mayor called Biden a “great friend of Detroit.”