In the case of The United States vs. FRIES, Mr. Justice CHASE said on the trial, and stated the opinion of the Court to be,
"That if a body of people, conspire and meditate an insurrection to resist or oppose the execution of any statute of the United States by force, they are only guilty of a high misdemeanor; but if they proceed to carry such intention into execution by force, that they are guilty of the treason of levying war; and the quantum of the force employed neither lessens or increases the crime – whether by one hundred or one thousand persons is wholly immaterial;"
https://www.nytimes.com/1861/01/25/archives/treason-against-the-united-states.html