A provision of the 1996 Communications Decency Act known as Section 230 was intended to protect free expression on the internet by shielding internet companies from liability for much of the content their users post on their platforms.Fact check:Justice Clarence Thomas didn't say Section 230 is unconstitutionalTweets:Supreme Court dismisses case questioning Trump's blocking of Twitter criticsThe case, Gonzalez v. Google, appeared designed to catch the attention of Associate Justice Clarence Thomas, who has questioned Section 230 in other contexts.The Supreme Court dismissed as moot a high-profile case last year about whether former President Donald Trump was on solid legal ground when he blocked several of his critics on Twitter back when he was in office."When a user does not already know exactly where to find something on the Internet – and users rarely do – Google is the gatekeeper between that user and the speech of others 90% of the time."Guide:A look at the key cases and questions pending before the nation's high courtPreview:Supreme Court to grapple with race, elections in new term as battle over abortion lingersMore:Supreme Court turns back effort by MyPillow CEO Lindell to toss $1.3 billion defamation suitContributing: Jessica Guynn"