This post has been updated here to reflect new developments.

The Connecticut Supreme Court ruled on March 15 that family members of nine victims of the 2012 Sandy Hook massacre can go to trial against Remington, the maker of the rifle used in the attack, and several other defendants in the gun industry.

Thursday’s ruling is the latest event in a legal battle that has been churning since 2014. And it only resolves the very simple question of whether the lawsuit should exist at all. No court has yet had an opportunity to address the question at the center of this case: Do Remington and its distributors and sellers actually bear some responsibility for the Sandy Hook shooting? The victims’ families are now one step closer to getting that question in front of a jury.

Where was the case before this ruling?

In 2016, a trial court judge, Barbara Bellis, found that a federal law called the Protection of Lawful Commerce in Arms Act barred the family members from seeking damages from the companies that made and sold a military-grade weapon to the Newtown shooter’s mother. The shooter used a Bushmaster XM15-E2S rifle to kill 26 people — including 20 elementary school children — in just over four minutes. (Bushmaster is owned by Remington, which claims to be America’s oldest gunmaker.)

What happened this week?

The Connecticut Supreme Court ruled that just one of the plaintiffs’ many claims could live to see another day. Lawyers for the Newtown families can now move forward with their argument that Remington marketed its products in an especially dangerous way. Timothy Lytton, a law professor at Georgia State University and PLCAA expert, describes the plaintiffs’ legal theory like this: “They’re saying that Remington was drawing high-risk people out of the woodwork to buy their product.”

Remington’s edgy marketing choices included promoting the Bushmaster XM15 as ‘‘the ultimate combat weapons system,” and touting its offensive capabilities. In advertisements, Remington depicted the gun in the hands of soldiers patrolling the jungle. One advertisement for the XM15-E2S included the slogan, ‘‘Forces of opposition, bow down. You are single-handedly outnumbered.’’

The families allege that Remington’s hyper-militaristic portrayal of the XM15 runs afoul of a Connecticut law that prohibits companies from marketing their products in unsafe and unscrupulous ways. That law is called the Connecticut Unfair Trade Practices Act (CUTPA), and it’s a run-of-the-mill consumer protection statute that exists in some form in every state.

The Connecticut Supreme Court thinks that this question — whether Remington’s marketing violated CUTPA — should go to a jury. If a jury finds that the gunmakers unscrupulously advertised a dangerous product, the gunmakers could be held liable for the deaths at Sandy Hook.

But wait … what about the gun industry liability shield?

Often, the federal PLCAA law means sudden death for any lawsuit against a gun company. But the statute has a few holes through which lawsuits can pass. If a gun maker or gun seller knowingly breaks the law, and there are injuries because of that violation, then victims can sue for damages. For example, it is a crime for a gun store to sell a weapon to a known felon, and the gun store can be sued if that felon uses it to kill people.

In this case, the plaintiffs are arguing that Remington’s unethical marketing violated the CUTPA and drew the Sandy Hook shooter to the weapon.

So what happens now?

Theoretically, Thursday’s ruling means that the case can, at long last, go to trial. But the defendants are almost certain to appeal, and they will be appealing directly to the Supreme Court of the United States.

The Supreme Court? This escalated quickly…

Only the U.S. Supreme Court can overturn the Connecticut Supreme Court’s determinations on its own state law. Lytton says that the defendants will file their petition as quickly as they can, hoping the justices will hear the case in the fall.

What will the gun companies be asking the Supreme Court to consider?

The Supreme Court will consider whether PLCAA kicks this case out of court for good. Remember a few moments ago when I said that victims of gun violence can get around the law and sue a gun manufacturer if it violated a law? Remington and the other Sandy Hook defendants will be asking the Supreme Court, “Well, violate what laws exactly?” (They’ll say it with more reverence and panache, of course.)

The gun company defendants will ask the Supreme Court to declare that gun companies can be sued only when they violate gun-specific laws. There are laws on the books that speak directly to the sale and distribution of guns, like prohibited purchaser laws. But then there are laws like Connecticut’s unfair trade practices law, which are broad trade regulations that address far more than just firearms. Are violations of either type of law a way around PLCAA? Federal courts are currently divided on this issue. (There’s more to this, and if your curiosity is piqued, please read this helpful explanation by Lytton in The Conversation.)

If the Connecticut Supreme Court’s approach stands, then the law protecting lawful arms sales is much more vulnerable than it has been in the past, and gun companies could potentially be exposed to a “flood of lawsuits across the country.” Remember, every state has its own CUTPA-like law. If, however, the gun industry gets its way, it will still be able to use PLCAA to deflect almost every lawsuit that comes its way. Keeping the federal law strong is a top policy priority for the gun lobby. When the law passed in 2005, Wayne LaPierre, the head of the National Rifle Association, called it “the most significant piece of pro-gun legislation in twenty years.”

Will the Supreme Court take the case?

Who knows! If anyone tells you they know, ignore them. Mark Joseph Stern of Slate made the excellent point that there’s a huge optics problem if SCOTUS intervenes and puts relief on hold for the families of the murdered. But likability is hardly the high court’s primary concern, and it’s absolutely possible that the Supreme Court will take up the case to settle the narrow legal issue of determining what kinds of lawsuits PLCAA permits.

What will happen to the trial in the meantime?

It will probably be put on hold. The trial court would be reluctant to move forward with discovery while it’s waiting to hear from SCOTUS.

What if the case goes to trial in Connecticut?

This would be a very big deal, because trials against gun companies rarely happen, thanks to the Protection of Lawful Commerce in Arms Act. This case would be one of a handful in which gun companies are forced to cough up documents on their manufacturing, marketing, and distribution practices. Those documents could answer some of the many open questions about the connection between above-board manufacturers and the black market for firearms. Right now, we only have hints about how gunmakers might facilitate the illicit gun trade.

It’s hard to say exactly what the Sandy Hook families could unearth through discovery in the Connecticut lawsuit, but we’re starting from a place of little knowledge. At oral argument in 2017, the lawyer for the families told a panel of judges, “Remington may never have known [the gunman], but they had been courting him for years.” The plaintiffs are looking for information that would tell them whether that is true.