During the first Democratic debate on Thursday night, front runner Joe Biden proposed banning the sale of any firearm that doesn't include theoretical biometric locks.

"We should have smart guns," Biden said. "No gun should be able to be sold unless your biometric measure could pull that trigger. It's within our right to do that. We can do that. Our enemy is the gun manufacturers, not the NRA."

While prototypes of guns with integrated biometric locks exist, none are currently for sale on the American market. Biden's proposal would effectively outlaw the sale of every firearm on store shelves in the United States.

Biden's call for a ban on the sale of traditional firearms was part of his comments on what gun control proposals he would support as president. He also appeared to support Congressman Eric Swalwell's call for a mandatory buyback program for so-called "assault weapons."

"I would buy back those weapons," Biden said. "We already started talking about that. We tried to get it done. I think it can be done. It should be demanded that we do it and that's a good expenditure of money."

Biden's comments did not make it clear if he supported making a buyback mandatory as Swalwell has proposed or if his support was limited to a voluntary buyback program. Earlier in the debate, only Swalwell and Kamala Harris raised their hands to indicate support for a system where gun owners are not given a choice on whether or not to sell their guns to the government and could face jail time if they do not.

Biden also touted his record on gun control in his comments.

"I'm the only person that's beaten the NRA nationally," Biden said. "I'm the guy that got the Brady Bill passed, the background checks. Number 2, we increased that background check during the Obama/Biden administration. I'm also the only guy that got ‘assault weapons' banned. Banned. And the number of clips in a gun banned."

It's unclear what action or legislation Biden was referring to when he said the Obama administration increased background checks. It's also unclear what the former vice president meant by "the number of clips in a gun" as clips are loading devices, not ammunition.