Sen. Cory Booker (D-NJ) sums up his ambitious new gun control plan in one sentence: “If you need a license to drive a car, you should need a license to own a gun.”

On Monday, Booker unveiled his proposal to tackle America’s gun problem as part of his bid for the presidency, detailing a plan that sets a high bar for the rest of the Democratic field.

His plan includes the typical Democratic proposals: universal background checks, an assault weapons ban, better enforcement of existing gun laws, and more funding for gun violence research.

But Booker’s plan goes further by requiring that gun owners not just pass a background check but obtain a license to be able to purchase and own a firearm. It’s a far more robust gun control proposal than any other presidential candidate has proposed. The idea has solid research behind it, and real-world experience in nine states that currently require a license or permit for at least handguns, including Booker’s home state of New Jersey.

The plan would go toward addressing a very serious issue: America currently leads the developed world in gun violence. One big reason for that is that America has the laxest gun laws — and the most guns — of any developed country. The research has consistently found that places with easier access to guns and more firearms have more gun deaths.

So far in the 2020 campaign, guns have not, surprisingly, gotten much attention. More than a year ago, the March for Our Lives movement that came out of the Parkland, Florida, school shooting revitalized America’s broader debate about guns, pushing the issue to the forefront in the 2018 midterm elections. But so far, 2020 Democrats have mostly stuck to a tried script on gun control, even as they push for fairly sweeping ideas in other areas, like single-payer health care, the Green New Deal, and dramatically hiking taxes on the superrich.

Booker’s proposal stands to change that. Not only is it the most sweeping gun control plan out of the 2020 Democratic candidates, but it’s among the most far-reaching of any presidential campaign ever.

Booker’s plan seeks to treat guns a bit more like cars

Booker’s proposal would require people to obtain a license to purchase and own a gun. To obtain a license, people would go to designated outposts — similar to the passport system — to get a federal license, administered by the FBI. Applicants would need to pay a fee; submit paperwork, a photo, and fingerprints; sit for an interview; pass a comprehensive background check; and go through gun safety training to get a gun. The license would be valid for five years, although it could be rescinded if someone breaks the law or otherwise proves to be a danger.

That’s similar to what states that currently mandate licenses for guns already do. Booker’s home state of New Jersey, for instance, requires that people obtain a permit from local or state police to buy a gun. The process entails extensive vetting in which applicants submit personal details (including about their past), go through a typical background check, and waive confidentiality for psychiatric and mental health records.

Booker’s plan would also let states go further than the federal requirements. For example, police in Massachusetts, which has arguably the most expansive gun laws in the country, have discretion to deny a license even if someone meets the explicit legal requirements for it. The idea behind this discretion is that there are some things that may not pop up in a person’s criminal or mental health record but are relevant to whether someone should be able to purchase and own a firearm — like, for instance, if police are constantly called to a man’s house for domestic disturbances, even if that man is never charged.

Booker’s plan doesn’t build in discretion, so the FBI wouldn’t have discretionary powers to deny a license. But it’s the kind of thing that states could do or keep doing on top of federal law. In general, the idea is to avoid interfering in states that already have a licensing scheme that’s equal to or stricter than Booker’s proposal.

Beyond licensing, Booker’s plan would also establish a national database to register and track guns. This, again, is a key component of Massachusetts’s law: By providing a way for law enforcement to track all guns in the state, they’re also able to know which weapons to take away if someone’s license is revoked due to, say, criminal activity.

Booker’s plan also includes a limit on purchases, allowing people to buy just one handgun a month. The idea is to stop people from going to places with looser gun laws, buying a lot of guns, and taking them back home to resell them illegally. Advocates of this proposal point to Virginia, where gun trafficking out of state reportedly worsened after the state repealed its purchasing limit.

And the proposal includes more typical Democratic ideas, including universal background checks, an assault weapons ban, and more stringent oversight of the gun industry.

Critics say that licensing and other restrictions put too much of a burden on gun owners. But in Massachusetts, for example, more than 95 percent of applicants get approval. While the process does take time and effort, advocates say it does a better job weeding out potential wrongdoers than simple background checks.

The ideas, from universal background checks to licensing, would require Congress to pass a bill — an unlikely ask as long as Republicans control either chamber. Should Congress not act, though, Booker also vows to use executive actions on day one to tighten gun laws as much as possible. But executive action is going to be much more limited, enacting changes at the edges rather than establishing sweeping proposals like a new gun licensing scheme.

If Congress were to follow Booker’s lead, however, it’d place a whole new layer of checks on buying and owning a gun in the US. And there’s evidence that would save lives.

Requiring a license to own a gun has strong research behind it

Booker’s pitch to go further on guns than the typical Democratic proposals is supported by much of the current research on gun policy.

On gun licensing, the big studies so far come out of Connecticut and Missouri. In Connecticut, researchers looked at what happened after the state passed a permit-to-purchase law for handguns — finding a 40 percent drop in gun homicides and a 15 percent reduction in handgun suicides. In Missouri, researchers looked at the aftermath of the state repealing its handgun permit-to-purchase law — finding a 23 percent increase in firearm homicides but no significant increase in non-firearm homicides, as well as 16 percent higher handgun suicides. All of that suggests that gun licensing saves lives.

Meanwhile, recent research has suggested that universal background checks — the most commonly touted idea by Democrats, largely because of their popularity — actually aren’t that effective on their own. Several studies from researchers at UC Davis, UC Berkeley, and Johns Hopkins have found that universal background checks alone at the state level and in urban counties were not linked to changes in firearm homicide or suicide rates.

Previously, the research base on background checks was limited but promising. A review of the evidence released by the RAND Corporation early last year looked at the best US-based studies for all sorts of gun policies, including background checks.

RAND found “limited” to “moderate” evidence that background checks in general reduce violent crime, including homicides, and suicides. But RAND also cautioned that the research just on closing the background check loopholes and making the system more comprehensive or universal was “inconclusive” when it came to firearm homicides. The newer studies fill in that gap — and they don’t look good for universal background checks.

In short: Establishing a background check system, as the US has already done on a national scale, likely has an effect. But making the system more comprehensive or universal doesn’t seem to have a significant effect on its own, at least at a population level. Researchers say that could be linked to several factors, from the difficulty of enforcing universal background checks to poor record-keeping for some states’ existing laws.

Similarly, other research has suggested that while an assault weapons ban may have some impact on the deadliness of mass shootings, it would have little to no impact in other areas. That’s in large part because the great majority of gun deaths — more than 70 percent of homicides — involve handguns, not assault rifles.

That’s not to say that the non-licensing measures would do nothing. In fact, universal background checks are an inherent part of the licensing systems that exist so far: Such background checks are necessary to verify that someone really should be able to obtain a license.

But licensing specifically would likely be far more effective than the typical proposals put forward by Democrats. A Johns Hopkins study, which found that comprehensive background checks alone correlated with more firearm homicides in urban counties, found that licensing systems were the one policy associated with fewer firearm homicides.

Until Booker’s plan, 2020 Democrats were generally playing it safe on guns

The Democratic primary has been filled with innovative new ideas on all sorts of policy issues. Thanks to Sen. Bernie Sanders’s (I-VT) advocacy in 2016, Medicare-for-all — or at least some sort of health care expansion — has set the terms of the debate on health care policy. There are also proposals like the Green New Deal to tackle climate change; Sanders’s estate tax expansion; Sen. Elizabeth Warren’s (D-MA) plans to institute a wealth tax, make college debt-free, lower generic drug prices, and tackle the opioid epidemic (Warren has quite a few ideas); Sen. Kamala Harris’s (D-CA) proposal to raise teacher pay; several anti-poverty ideas; and much more.

But on guns, the 2020 candidates have, until Booker’s plan, generally stuck to old ground. The candidate supposedly focused on guns, Rep. Eric Swalwell (D-CA), has mostly spoken about background checks and an assault weapons ban. Harris’s widely touted gun proposal would just use executive actions to, in effect, expand background checks and enforce existing gun laws.

In a primary that’s supposed to be all about fresh ideas, some gun control advocates have found the lack of big thinking disappointing.

“You have progressives who are running for president talking about single-payer, talking about Green New Deal, talking about breaking up large tech companies, talking about a super surcharge on multi-multi-millionaires,” Igor Volsky, the executive director of Guns Down America, told me prior to Booker’s proposal. “On an issue that is so important to so many Americans — the issue of guns — it’s unconscionable to me that the solutions we’re hearing from the folks running for president are focused on incremental reforms that they’ve been selling for the last 20 years.”

If nothing else, the lack of ideas on guns has pushed away the attention that could be going to gun violence in a Democratic primary — because it’s hard to debate an issue when all the candidates’ proposals are basically the same. As Peter Ambler, executive director of the advocacy group Giffords, previously told me, “The candidates have so little contrasts on the issue that it’s going to dampen the attention that the candidates themselves pay to the issue and dampen the news media coverage of the issue.”

One reason for sticking to the old policies is that they still haven’t happened after all this time. If an idea like universal background checks — that consistently polls above 80 percent support — can’t get through Congress, why bother with even more ambitious proposals?

But the thinking, as Volsky details in his book Guns Down: How to Defeat the NRA and Build a Safer Future with Fewer Guns, is to start pushing the country over time toward where gun control advocates would like to see the issue go: Just like Sanders helped move Democrats toward supporting single-payer health care plans, and just like the LGBTQ movement slowly pushed the nation toward backing same-sex marriage, gun control advocates should use moments like 2020 to move toward their ideal agenda.

“We need a fundamentally different approach in the next 20 years,” Volsky said. “We need to ask for what we really want, not what we think moderate, centrist voters would go for. In the book, I argue that should be a future with fewer guns.”

Besides, ideas like gun licensing do appear to have strong support. Surveys have found that more than 70 percent of Americans, including a majority of gun owners, support requiring a license to buy a gun. That suggests there’s room for Democrats to go further.

No one was really making that push in the 2020 primaries. That changed with Booker’s plan.

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