Leading up the recent mass shooting in Buffalo, New York, that killed 10 people and wounded three others, the shooter used a private forum on the messaging platform Discord to document his ideology and attack plans, only inviting a small group of others to join shortly before the shooting.

When the shooting began, the perpetrator streamed the act to the video-streaming site Twitch. In the aftermath, investigators determined that the shooter had been inspired to act at least in part by racist memes and discussions shared on the anonymous message boards, 4chan and 8chan. Prior to the event, the shooter posted a 180-page diatribe to 4chan, detailing his reasoning and his plans.

Now, each of these tech companies is under investigation by the New York attorney general's office regarding the alleged role they play in fomenting violence. The investigation came at the request of NY Governor Kathy Hochul.

"Time and time again, we have seen the real-world devastation that is borne of these dangerous and hateful platforms," Attorney General Letitia James is quoted in a statement, "and we are doing everything in our power to shine a spotlight on this alarming behavior and take action to ensure it never happens again."

Discord said that the violent and racist forum used by the shooter was only revealed to other users when they were invited by him in the lead-up to his attack. Amazon (AMZN  ), the owner of Twitch, said that the shooter was only able to stream for two minutes before his access was shut down, but screenshots from the footage taken in those two minutes have been spread across the internet.

"The terror attack in Buffalo has once again revealed the depths and danger of the online forums that spread and promote hate," James said. "The fact that an individual can post detailed plans to commit such an act of hate without consequence, and then stream it for the world to see is bone-chilling and unfathomable."

Currently, social media platforms are provided broad protections under U.S. law, making it difficult to hold them responsible for any violence promoted on their sites. Exceptions to the law, the Communications Decency Act Section 230, include posts that violate federal laws.

"If a suspect commits a federal hate crime and prosecutors also name an online service as a defendant, Section 230 categorically does not apply to them," Professor Eric Goldman of Santa Clara University School of Law said. "However, the odds that an internet service would be held liable for a user's hate crimes are very, very low."

According to Goldman, in order to hold a company accountable for posts made on their site, you would have to prove that the company had sufficient knowledge of the criminal actions, knowledge beyond a simple awareness of the fact that the crime is taking place on their platform.

For their part, Twitch and Discord both say that they're cooperating with investigations, and both have issued statements of condolences. However, neither has suggested they hold any responsibility for the event.

"Bigotry and hate don't happen in a vacuum," Twitch wrote in a statement. "They're enabled by a permissive culture when we don't create spaces where people feel empowered to speak up."