Somerset, the new Protector, strove to govern on the basis of civil liberty and religious tolerance.
Throughout the war, too, he was so intensely concerned about states' rights and civil liberty that he opposed the exercise of extra-constitutional war powers by President Jefferson Davis lest the freedom for which the South was fighting should be destroyed.
From 1858 to 1863 he was in the lower house of Congress, where he was noted for his strong opposition to the principles and policies of the growing Republican party, his belief that the South had been grievously wronged by the North, his leadership of the Peace Democrats or Copperheads, who were opposed to the prosecution of the war, and his bitter attacks upon the Lincoln administration, which, he said, was destroying the Constitution and would end by destroying civil liberty in the North.
Three of the four judges allowed the defence of the cardinal to be valid; but it was held that the papal rescript upon which he relied for his extraordinary powers as delegate was illegal under statute; and the lord chief justice decided that the plaintiff could not renounce his natural and civil liberty.
He had from the first been strongly opposed to the war, and in 1776 he published a pamphlet entitled Observations on Civil Liberty and the Justice and Policy of the War with America.