Former Vice President Joe Biden and Sen. Cory Booker went head-to-head Wednesday over legalizing marijuana, with the senator joking that Biden "might have been high" when he recently said he opposes federal legalization.

What they're saying: Booker called Biden out, stating: "I have a lot of respect for the vice president. He has sworn me into my office, and he's a hero. This week I heard him literally say that I don't think we should legalize marijuana. I thought you might have been high when you said it... because marijuana in our country is already legal for privileged people..."

Biden quipped back: "I think we should decriminalize marijuana, period, and anyone who has a record should be let out of jail, their record expunged, be completely zeroed out. But I do think it makes sense based on data that we should study what the long-term effects are for the use of marijuana."

Catch up quick: Biden is the sole Democrat in the 2020 field who opposes legalizing marijuana at the federal level. The former V.P. said at a town hall Saturday that there would need to be more research into marijuana's effects before he'd ever legalize it as president, in order to rule out whether it's a "gateway drug."

He later clarified his stance on the drug in a tweet following online backlash from his 2020 competitors.

Of note: The House Judiciary Committee passed legislation Wednesday that would decriminalize marijuana at the federal level, CBS reports.

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