Where the 2020 Democrats Stand on Gun Control

Former Vice President Joseph R. Biden Jr. endorsed a national assault-weapons buyback program for the first time on Monday night, joining other Democratic presidential candidates in calling for new gun control measures in the wake of two mass shootings over the weekend that left 31 people dead.

In an interview on CNN, Mr. Biden also reaffirmed his support for universal background checks on new gun purchasers and for a ban on assault weapons. And on Tuesday morning, Mayor Pete Buttigieg of South Bend, Ind., released his own plan aimed at curbing gun violence and extremism, proposing a nationwide gun licensing system.

As the nation reels from the shootings in El Paso and Dayton, Ohio, many of the 2020 contenders are eager to explain what they would do about gun violence if elected president. While the field of two-dozen hopefuls has largely agreed on a set of ideas that Democrats have been trying to advance unsuccessfully for decades, some candidates have latched onto more progressive policies that previously might not have been politically palatable.

Senator Cory Booker of New Jersey, who already released a gun control plan in May, is expected to deliver a major speech on gun violence on Wednesday morning. He has also called for a federal gun licensing program, one of the more progressive proposals in the field.

Under a gun licensing program, a person seeking to buy a firearm would need to apply for a license in much the same way one applies for a passport. Such a program would set minimum standards for gun ownership nationwide.

Mr. Booker’s 14-part plan to combat gun violence has a gun licensing program as its centerpiece. His campaign has said the process would involve submitting fingerprints and sitting for an interview, and would require applicants to complete a certified gun safety course. Each applicant would also undergo a federal background check before being issued a gun license, which would be valid for up to five years.

Now Mr. Buttigieg and Mr. O’Rourke also back such a plan. Former Gov. John Hickenlooper of Colorado expressed his support for gun licensing in a plan he released a few weeks after Mr. Booker’s.

Research has shown that background checks and assault weapons bans, when implemented at the state level, are not nearly as effective at reducing gun homicides and suicides as gun licensing programs for purchasers. A study published in 2018 found that 63 percent of gun owners supported requiring a person to obtain a license from a local law enforcement agency before buying a gun; support for gun licensing among people who do not own a gun was even higher.

Representative Eric Swalwell of California is no longer running for the 2020 nomination. But when he was, he made gun control his signature issue and put the idea of a nationwide buyback program for assault weapons on the table.

Mr. Swalwell’s buyback program would have been mandatory; his plan suggested that the government criminally prosecute anyone who refused to comply.

In an interview on “Pod Save America” on Monday, Mr. O’Rourke said he would support a mandatory buyback program. Mr. Biden, in his comments Monday night, appeared to endorse a voluntary approach.

“Right now, there’s no legal way that I’m aware of that you could deny them the right” to own an assault weapon if it had been legally purchased, Mr. Biden said.

Many of the candidates agree on other measures aimed at curbing gun violence.

In addition to background checks, red-flag laws and an assault weapons ban, several candidates — including Mr. Buttigieg, Ms. Harris and Mr. Delaney — want to close the so-called boyfriend loophole. Doing so would bar people under a restraining order or who were convicted of abusing, assaulting or stalking a domestic partner from buying guns.

Most of the candidates who have released specific plans on gun violence also support measures such as banning high-capacity magazines, funding gun-violence research and raising the age to purchase a firearm to 21.

“We cannot continue to live in this reality,” Mr. Booker wrote in an email to supporters late Sunday. “There are so many steps we can take to end this uniquely American problem.”