The Supreme Court is set to hear back-to-back oral arguments Tuesday and Wednesday on two cases that could significantly reshape online speech and content moderation.

The outcome of the oral arguments could determine whether tech platforms and social media companies can be sued for recommending content to their users or for supporting acts of international terrorism by hosting terrorist content. It marks the SCOTUS’ first-ever review of a hot-button federal law that largely protects websites from lawsuits over user-generated content.

First up Tuesday is the Gonzalez v. Google case. At the heart of the legal battle is Section 230 of the Communications Decency Act, a nearly 30-year-old federal law that courts have repeatedly said provide broad protections to tech platforms but has since come under scrutiny alongside growing criticism of Big Tech’s content moderation decisions.

The case involving Google zeroes in on whether it can be sued because of its subsidiary YouTube’s algorithmic promotion of terrorist videos on its platform.

According to the plaintiffs in the case — the family of Nohemi Gonzalez, who was killed in a 2015 ISIS attack in Paris — YouTube’s targeted recommendations violated a US antiterrorism law by helping to radicalize viewers and promote ISIS’s worldview.

The allegation seeks to carve out content recommendations so that they do not receive protections under Section 230, potentially exposing tech platforms to more liability for how they run their services.

Google and other tech companies have said that interpretation of Section 230 would increase the legal risks associated with ranking, sorting and curating online content, a basic feature of the modern internet. Google has claimed that in such a scenario, websites would seek to play it safe by either removing far more content than is necessary, or by giving up on content moderation altogether and allowing even more harmful material on their platforms.

Friend-of-the-court filings by Craigslist, Microsoft, Yelp and others have suggested the stakes are not limited to algorithms and could also end up affecting virtually anything on the web that might be construed as making a recommendation. That might mean even average internet users who volunteer as moderators on various sites could face legal risks, according to a filing by Reddit and several volunteer Reddit moderators. Oregon Democratic Sen. Ron Wyden and former California Republican Rep. Chris Cox — the original co-authors of Section 230 — argued to the court that Congress’ intent in passing the law was to give websites broad discretion to moderate content as they saw fit.

The Biden administration has also weighed in on the case. In a brief filed in December, it argued Section 230 does protect Google and YouTube from lawsuits “for failing to remove third-party content, including the content it has recommended.” But, the government’s brief argued, those protections do not extend to Google’s algorithms because they represent the company’s own speech, not that of others.

The Supreme Court will hear oral arguments Wednesday on the second case, Twitter v. Taamneh, which will decide whether social media companies can be sued for aiding and abetting a specific act of international terrorism when the platforms have hosted user content that expresses general support for the group behind the violence without referring to the specific terrorist act in question.

Rulings in the cases are expected by the end of June.