Facebook tried to ban gun sales 4 years ago. It’s still trying.

In early 2016, Facebook took a political stand unlike any it had before, prohibiting private gun sales on its website. Four years later, the fallout — gun enthusiast groups moving into the shadows where sales remain common, sellers gaming the Marketplace feature, and the well-documented use of coded language by gun owners — demonstrates how difficult it is for Facebook and other platforms to monitor and control the powerful forums they provide.

Before the ban, arranging peer-to-peer gun sales, which are allowed under federal law but outlawed in more than a dozen states, had become popular on Facebook, where users flocked to "Buy, Sell, Trade" groups in their area to find lots of buyers and sellers and few questions. The company's decision to eliminate these sales followed intense political pressure in the wake of the massacre at Sandy Hook Elementary School, when gun control advocates failed to persuade Congress to enact universal background checks, allowing gun owners in most states to continue selling firearms without government involvement.

Agreeing that unregulated sales represented a potentially dangerous loophole, Facebook executives in January 2016 took it upon themselves to shut down the sales on both Instagram and Facebook. But users quickly found workarounds, with sellers posting photos of a gun with accompanying language designed to shift the sales conversation to private message. While Facebook's policy led to the removal of some high-profile groups that hosted these discussions, many simply moved to unlisted settings that made tracking the behavior more difficult.

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Today, as Facebook faces intense scrutiny from lawmakers and the public, the same basic workarounds are still being used to arrange gun sales. In fact, if you know where to look, deals are easy to find.

Take the Virginia Gun Enthusiasts group, a private group made up of more than 800 members and created on Jan. 29, 2016, the same day Facebook announced it was banning private gun sales arranged on the site. The group's description, which closely mimics countless others across the country, establishes the ground rules: "No private gun sales are allowed. Any firearms listed with a price will be deleted and you will be removed from the group. PICTURES ONLY." Members are urged to "PM ONE ANOTHER," a reference to private messaging.

A stream of recent posts shows the system works just as intended. There's a photo of a 9mm Glock pistol with a matching holster under the words "Not for sale or trade just want to have a discussion." I message the user to ask if the gun is for sale. "Im mostly looking to trade it," he replies, before adding, "I am open to cash offers."

I click back to the group feed and find a photo of a Smith & Wesson .357 revolver, this time posted under the shorthand "NFS or NFT…," meaning Not For Sale or Not For Trade. I again message the user to see if the gun is for sale. "Asking 900.00 for it," he confirms, adding that it's "a super nice hand gun."

Before I can reply, another member of the group has posted photos of an AR-15-style semiautomatic rifle, under the words "Not for sale or for trade!!!!" Undeterred, I message my fellow group member to see if he's open to cash offers. "Looking for 600 FIRM," he responds.

Digital swap-meet

The posts demonstrate how difficult it is for Facebook to prevent its more than 2 billion users from privately exchanging firearms and, more broadly, anything. As long as a seller is able to evade Facebook's keyword-based algorithm, and no other user reports a post as suspicious to trigger a review by one of Facebook's low-wage moderators, it's easy to solicit a potential buyer and move the conversation to private message. Think of it as a digital swap-meet, where the display cases are monitored but all sales are completed under the table, cloaked in privacy.

At the same time, Facebook must contend with users skirting the rules on its Marketplace platform, its in-house version of Craigslist. Recent media reports have shown how prevalent gun sales are on Marketplace, where sellers covertly list firearms by posting a photo of a case or another accessory at an inflated price, evading Facebook's automated listing detection. The resulting deals are hiding in plain site.

Gun sales are a particularly fraught moderation challenge for Facebook, in part because the company brought it upon itself. By banning the sale of a product already subject to government regulation, Facebook inserted its own politics, siding with California and New York and several other states in doing what lawmakers in Washington had opted not to do — despite wide public support for universal background checks. (Licensed gun stores in every state must conduct a background check before selling a firearm. In some states, such as Facebook's home in California, gun owners are legally required to sell their weapons through licensed dealers. Most states, however, allow gun owners to sell firearms freely.)

"If we catch someone selling guns on Facebook, we take immediate action," a Facebook spokesperson said in a statement for this story. "Over 93% of the firearm sales content we remove is detected proactively, which is why we continue investing in our detection and reporting systems."

To understand how Facebook's effort to eliminate private gun sales has unfolded over the past four years, I called former Facebook engineer Chuck Rossi, who during a 10-year career at the company became its self-described "resident gun expert." I first met Rossi in a secret Facebook group, naturally, where he was an administrator with a more formal version of a role he still assumes today: advocate for gun enthusiast groups and gun store owners who have their pages removed or suspended. Rossi drew criticism when I made his role public in May 2016, including from his Facebook colleagues, many of whom saw his work as at odds with the company's progressive stance.

The most challenging part of enforcing Facebook's gun sales ban, Rossi said, is the sheer volume of content posted to the site every day. "The Facebook playbook was to get it down to a level that was acceptable," he explained. "Because to do more would intrude on the ethos of the product. To review every single PM, post, comment … that level of scrutiny is just not reasonable."

It's difficult to quantify how many guns are sold on Facebook today, because many deals take place within groups that are invite-only or unlisted. This makes it less likely for members to have their posts reported as suspicious by fellow users, leaving Facebook's algorithm as the primary mechanism for removal.

To be sure, Facebook has taken down a lot of suspected gun offerings in recent years. The company reported removing roughly 2.3 million pieces of firearm sales content in the third quarter of last year alone. Facebook disclosed similar figures in a September 2019 response to a list of pointed questions by U.S. Sen. Robert Menendez of New Jersey. The line of questioning was the latest in a series of inquiries from Congress over gun sales on Facebook, typically following media reports demonstrating the ineffectiveness of its ban. Each time, Facebook executives say the company is trying to do better.

"We are continuously updating our automated systems and the signals analyzed by human reviewers to catch violating content, including keywords," wrote Kevin Martin, Facebook's vice president of U.S. public policy, in a Sept. 26 letter. These models are constantly updated based on learnings and action taken from the human reviews."

And yet, as virtually any gun owner who has tried to sell a weapon on Facebook knows, the system is far from perfect. The way it works hasn't fundamentally changed since Facebook introduced its ban, either.

"Enforcement would work the same as everything else on Facebook," a company spokesperson explained in 2016. That is: users report suspected policy violations, which are then reviewed by Facebook moderators who take down content in an unabating game of whack-a-mole.

Therein lies the issue. Facebook's algorithm is the first line of defense, scanning for keywords like "sale" and "offer." It's a start, Rossi says, but it's not going to be able to catch savvy sellers intent on breaking the rules. And it's a prime example of how difficult moderating content of any kind can be for Facebook.

After this story was published, Sen. Menendez responded with a scathing statement: "The fact that a former Facebook employee recognized that the company's real intentions were not to completely avoid gun sales on its platform, but to reduce them to some 'acceptable' level, is baffling. No level of gun sales on Facebook or any other social media platform is acceptable. Period. If Facebook — and others — cannot enforce their own policies, we need to seriously discuss whether a federal response may be the only way to address this increasingly worrying issue."

The current reality, where gun sales that once took place in the open on Facebook have been pushed into the shadows, was predictable four years ago, yet few discussed it openly at the time. Instead, gun control advocates claimed a philosophical victory, moving on to other policy battles while gun owners and staunch Second Amendment defenders quietly established workarounds.

Further complicating matters is that keeping private gun sales off Facebook is only part of the company's challenge. Facebook allows traditional, regulated gun stores to maintain a presence on the platform, and faces both political and business pressure to ensure that licensed merchants aren't removed.

This is where Rossi comes in. Though he left Facebook in 2018 (he now works at Anduril Industries, the defense industry startup launched by Oculus founder Palmer Luckey), Rossi continues to volunteer his time to help licensed gun stores get back on Facebook and Instagram. He recalls an incident last year when Springfield Armory, one of the country's oldest large-scale gun manufacturers, had its Instagram page shut down just days before the SHOT Show, the gun industry's biggest trade show of the year.

"I did an all hands on deck," Rossi said. "I called back in [to Facebook] and said, 'Listen guys, this is nuts.'"

Eventually, Rossi helped get Springfield Armory's page restored. But the incident is far from isolated. Rossi said he's constantly alerted to the removal of brick and mortar gun-store Facebook pages.

"I've gotten back so many dinky mom and pop shops, who are abiding by the rules, but because of the shitty algorithm, they just take down the account," Rossi said. "You can't run a business without a social media presence."

Private messages off-limits

In both cases — the gun owner who seeks a sale with a thinly veiled post and the gun store that has its page removed — the weak link for Facebook has been training artificial intelligence to recognize coded language, such as "Not for sale" or "Open to discuss." Rossi helped write the training deck for moderators, and reviewed how Facebook applied its AI in the early days of the ban. He recently wrote a blog post about his experience for a gun rights organization he helps lead, called Open Source Defense.

Social media platforms "have been inconsistent, unclear, and unhelpful when it comes to their content and ads policies" regarding guns, Rossi wrote. "They seem to be optimizing for removing firearm content as something unimportant and unwelcome on their platforms."

Across the political spectrum, virtually no one is advocating for Facebook to spy on users' private messages. This makes it difficult to police user activity taking place just below the surface.

"This is a larger issue of privacy," said David Chipman, a senior policy analyst at the Giffords Law Center, which advocates for stricter gun regulation. "Where do we draw the balance of protecting the privacy of individuals but not make it easy for criminals to do what we don't want them to do?"

Meanwhile, the political pressure on Facebook has waned, as the network faces larger concerns about its role in the previous and upcoming presidential elections. Four years on, the question remains: Does Facebook have the ability, or the incentive, to completely eliminate private gun sales on its platforms?

"No," Rossi said without hesitation. "It's just not worth the effort. The money it would take would be completely draconian. It would hurt the platform."

Back online, in the Virginia Gun Enthusiasts group, members trade links to news articles and memes about the political battle happening in the state's capital. Democratic Gov. Ralph Northam declared a state of emergency last month in advance of a rhetorically charged protest over a slate of gun-control bills Northam backed. Militia members and others turned out bearing guns and flags, but the rally proved uneventful.

As the news cycle marches on, new posts are added to the group daily. It remains a good place to find a cheap used gun. But if you don't act quickly you might miss out, as I discover when I message a user who posted pictures of a .45-caliber Desert Eagle pistol under the letters "Nfs/nft." (Not for sale/not for trade.)

I ask if he is taking offers for the gun. He writes back: "Its sold."

This story was updated Feb. 12 to add information about Sen. Menendez's reaction.