Originally Posted by
SonicFlyer
There is a theory out there that the 16th Amendment wasn't lawfully ratified. I'm 85% sold on it, but not 100%.
The Court already settled it when they heard Brushaber. Had it not been lawfully ratified, the pleading would have been invalid and never legally binding and the Court would have stated that. Instead the Court heard the case and decided, which procedurually settled the question.