The Wisconsin Supreme Court ruled earlier this week that Armslist.com may be held liable in the 2012 shooting of a woman and several of her co-workers, allegedly by her husband after the private purchase of a firearm from the website. The buyer was originally denied the purchase of a firearm after a failed background check due to the conviction of domestic violence.

Buyers can list firearms available for private sale on the website and are responsible for their own transactions.

Reversing a lower court’s ruling, the Wisconsin Supreme Court found that Armslist.com isn’t protected by the Communications Decency Act of 1996, which largely immunizes online service providers from responsibility for posts by third-parties.

The act provides immunity to website operators, such as Armslist, only when the allegations treat the website as the publisher or speaker of third-party content,” the court said Thursday in its unanimous ruling. “The act does not protect a website operator from liability that arises from its own conduct in facilitating user activity.

Armslist’s website includes a notice at the bottom of the homepage telling users to “always comply with local, state, federal and international law” and says the company does “not become involved in transactions between parties.”

Some firearm enthusiasts worry that it sets a precedent for other courts to follow suit.

Other courts have heard similar cases but found Armslist not guilty (for example, in Chicago 2014). At the time, a judge said “Armslist permitted Ladera to place an advertisement on its website and nothing more. It did not invite Ladera or Smirnov to break the law. Alex’s allegations fall short of alleging any cognizable negligence claim for which Armslist could be held responsible for Smirnov’s acts.”

No word as of yet on how the current ruling will alter future private transactions through the website or if any further legislation finding sellers liable in similar sales may be created as a result.