Social media platforms such as Facebook and Twitter provide an opportunity for everyone to have a voice on the Internet, to communicate with friends, post their views, and comment on movies or the president. However, the fact that they provide a broad, open platform for speech doesn’t automatically mean they are “public forums” in the sense your town’s official Facebook page or @realDonaldTrump are. Those are run by the government or its officials, who, when it comes to the First Amendment, are “state actors” and can’t block people from the forum without complying with First Amendment standards. Facebook and Twitter, on the other hand, are platforms created and run by corporations, which are private entities that can curate and edit content.

The distinction between private entities and state actors providing forums for communication is crucial for the free speech rights of Internet users and the platforms they use. In a brief filed yesterday in a case before the U.S. Supreme Court, we explained that private entities do not become state actors simply by providing their own platforms for use by other speakers.

The case before the court, Manhattan Community Access Corp. v. Halleck, doesn’t actually involve social media platforms—it’s about whether a public access television station is a state actor that violated the First Amendment rights of two producers by taking down their videos that criticized the station. But the court’s decision could have a profound impact on online speech. Here’s why: the television station is operated by a privately owned nonprofit. The State of New York has no control over or say in the station’s content. It does appoint two of the nonprofit’s 13-member board of directors. A lower court ruled that the station was an arm of the state actor and couldn’t block the videos.

Although EFF does not have a position on whether the public access broadcaster in the case is a public forum, our brief urges the Supreme Court to rule narrowly and take great care in writing its opinion. We want to make sure nothing the court says in this case can be used in unintended ways in the far different context of privately operated Internet platforms. A broadly written opinion, adopting a low threshold for governmental involvement, could threaten the First Amendment rights of platform operators to curate content, and could give the government power to dictate content moderation rules and control what platforms can and can’t publish. As we explain in the brief, the rights of Internet users to both unmoderated and moderated platforms will suffer.

We weighed in on this issue last month in a case involving YouTube. There we explained that existing law—whereby privately run platforms are not constitutionally compelled to publish any users’ speech—allows for both unmoderated and moderated platforms. We believe this serves Internet users and human rights best.

In our brief yesterday we argue that, in order for a private entity’s speech platform to be considered a state actor, the government has to have created the forum, or run it, or exercise control over who administers it. Being regulated by government isn’t a significant enough connection to transform a private entity into a state actor—the government must have a significant role in controlling the operation or use of the forum. This is the proper standard to protect online speakers and ensure that private operators of online forums remain exactly that: private operators.