Who determines the "trutfullness" of free speech?

[metalman]

the amicus brief of the Cato Institute and P.J. O'Rourke in Susan B. Anthony List v. Driehaus, the Supreme Court case that asks the question "Can a state government criminalize political statements that are less than 100% truthful?"

footnote 15:

[Rep. Steven] Driehaus voted for Obamacare, which the Susan B. Anthony List said was the equivalent of voting for taxpayer-funded abortion. Amici are unsure how true the allegation is given that the healthcare law seems to change daily, but it certainly isn’t as truthy as calling a mandate a tax.​

brief includes mockery of the Justices who will decide the case