The OP mainly concerns the First Amendment, but the recent controversies around lying and free speech have not involved government attempts to stifle lies. IMO

The OP mainly concerns the First Amendment, but the recent controversies around lying and free speech have not involved government attempts to stifle lies. IMO, it's not possible for there to be a workable legal ban against lying in general; the "collateral damage" would be too great. Through there are are very many cases where specific kinds of lies could be made illegal. HOWEVER, for free speech to work, I think it's supremely important for everyone in society to do whatever they can to suppress lies, liars, and falsehoods. If that's not done, at best, the public square will degrade to being little more than a useless Library of Babel [1]. Unfortunately, a lot of people nowadays can't seem to tell the difference between a dissenting perspective and a lie, and that position ultimately discredits free speech. [1] https://en.wikipedia.org/wiki/The_Library_of_Babel; https://en.wikipedia.org/wiki/The_Library_of_Babel; "In any case, a library containing all possible books, arranged at random, might as well be a library containing zero books, as any true information would be buried in, and rendered indistinguishable from, all possible forms of false information..."