On Thursday, President Trump signed an executive order that could be used to punish social media companies, including Twitter, for how they monitor content. This comes after Twitter on Tuesday took the unprecedented step of adding a fact-check label to two tweets in which Trump erroneously attacked mail-in voting. Meanwhile, Facebook CEO Mark Zuckerberg on Thursday defended his company’s refusal to regulate misinformation — including false and deceptive political advertisements. Zuckerberg spoke with CNBC.

Mark Zuckerberg: “I don’t think that Facebook or internet platforms, in general, should be arbiters of truth. I think that’s a kind of a dangerous line to get down to in terms of deciding what is — what is true and what isn’t.”