Over the past week, Facebook and Twitter have codified a dual-class system for free speech: one set of rules for politicians or "world leaders," another for the rest of us.Why it matters: Social media platforms are privately owned spaces that have absorbed a huge chunk of our public sphere, and the rules they're now hashing out will shape the information climate around elections for years to come. Why now? President Trump's campaign placed ads this month that made false statements about Democratic candidate Joe Biden. Biden's campaign asked media outlets and digital platforms to stop running the ads; CNN took then down, but Facebook kept them up.Then Sen. Elizabeth Warren provoked Facebook with a deliberately misleading Facebook ad that claimed the company had endorsed Trump — before admitting that was a ruse to expose flaws in Facebook's policy. Facebook kept that ad up, too. Meanwhile, over on Twitter, Sen. Kamala Harris has been demanding that Trump's account get the boot for the president's repeated attacks on the Ukraine whistleblower, among others.The big picture: Online forums have always faced fights over "where you draw the line." But now that the troll vs. moderator game is being played on the stage of national politics, neither Facebook nor Twitter wants to play at all. Their solution: carve out some special rights for politicians.How it works on Facebook Facebook's policy lets politicians make just about any claim they want, in ads or posts, including repeating verbatim a false claim that has already been labeled elsewhere as false. That means they can misstate their own record or that of an opponent.What pols can't say in Facebook ads or posts: They can't misstate details about the voting process, such as when an election is taking place, the rules or how to vote.Their ads can't include profanity, as Trump's campaign found out.They can't embed social media posts that have been flagged by a fact-checker.While not held to standards on factual matters, they have to follow Facebook's other community standards, such as those on hate speech.Between the lines: It gets even messier, as politicians can take an already debunked claim and repeat it in their own ads. A regular user, meanwhile, can't take a false claim from a politician's ad and repeat the same words without violating Facebook's rules. They are, though, free to share that politician's ad.How it works on TwitterTwitter defines a class of "world leader" users who "are or represent a government/elected official, are running for public office, or are being considered for a government position," and who also have more than 100,000 followers and are verified.In theory, world leaders are supposed to follow the rules that apply to everyone else. That would mean no threats of violence, no promoting terrorism, no engaging in targeted harassment, and no harassing people of a particular race, religion, sexuality or gender.But Twitter says it may leave up the posts even if politicians break the rules due to the "newsworthiness" of their comments.The company says it reserves the right to limit the promotion of such tweets and to prominently note that the content has violated Twitter's rules. But it hasn't ever taken this step since announcing the policy in June.The bottom line: Each platform's rules have their own quirks. But both are dividing their users into two groups — and giving one of them fundamentally broader freedom to violate ethical and social norms in their postings and not be penalized.The outlier: Google-owned YouTube says its policies are not "speaker-based" but aimed at content. "Everyone that uploads videos on YouTube is subject to our policies, including politicians," according to YouTube spokesperson Farshad Shadloo. Go deeper: The misinformation age2020 misinformation threats extend beyond RussiaHuman actors are changing the spread of disinformationWelcome to our new synthetic realities