New Jersey Sen. Cory Booker took aim at former vice president Joe Biden at Wednesday evening’s Democratic presidential debate over marijuana policy—and even accused him, facetiously, of smoking it.

“I heard him literally say ‘I don’t think we should legalize marijuana,’” Booker said of Biden. “I thought you might have been high when you said it.”

Biden responded that he supports decriminalizing marijuana, “and anyone who has a record should be let out of jail, their record expunged, be completely zeroed out.” But in the exchange Booker landed a clean hit on the frontrunner for the Democratic presidential nomination in the latter stages of Wednesday’s debate in Atlanta.

Biden said at a campaign event in Las Vegas over the weekend that he supports decriminalizing marijuana for recreational use, but “before I legalize it nationally, I want to know a lot more about the science behind it.” He reiterated that position at the debate.

Booker cast that position as legitimizing the war on drugs, which he described as “a war on black and brown people.”

“Marijuana in our country is already legal for privileged people,” Booker said. “There are people in Congress right now that admit to smoking marijuana, while there are people—our kids are in jail right now for those drug crimes.”

The exchange came in the midst of a discussion about how candidates would attempt to speak and appeal to the African American community. “I have a lifetime of experience with black voters,” Booker quipped. “I’ve been one since I was 18.”

Biden sought, as he has repeatedly on the campaign trail, to tie his candidacy to Barack Obama’s legacy and popularity, particularly among African Americans.

“I’m part of the Obama coalition,” Biden said. “I come out of the black community in terms of my support. If you notice, I have more people supporting me in the black community, that have announced for me, because they know me, they know who I am.”

Biden has indeed dominated the Democratic field in black support. But on the issue of marijuana legalization, his views appear to trend more conservative than most Democratic voters. According to a Pew survey published last week, nearly four in five Democrats and Democratic-leaning independents favor full legalization.