degree of prudence would justify a shot one or two seconds too soon rather than a fraction of a second too late.  Upon our minds the evidence leaves no doubt whatever that the homicide was fully justified by the circumstances.  Neagle on the scene of action, facing the party making a murderous assault, knowing by personal experience his physical powers and his desperate character, and by general reputation his life-long habit of carrying arms, his readiness to use them, and his angry, murderous threats, and seeing his demoniac looks, his stealthy assault upon Justice Field from behind, and, remembering the sacred trust committed to his charge—­Neagle, in these trying circumstances, was the party to determine when the supreme moment for action had come, and if he, honestly, acted with reasonable judgment and discretion, the law justifies him, even if he erred.  But who will have the courage to stand up in the presence of the facts developed by the testimony in this case, and say that he fired the smallest fraction of a second too soon?

“In our judgment he acted, under the trying circumstances surrounding him, in good faith and with consummate courage, judgment, and discretion.  The homicide was, in our opinion, clearly justifiable in law, and in the forum of sound, practical common sense commendable.  This being so, and the act having been ’done * * * in pursuance of a law of the United States,’ as we have already seen, it cannot be an offense against, and he is not amenable to, the laws of the State.”

The petitioner was accordingly discharged from arrest.

[1] NOTE.—­I find the following apt illustrations of this doctrine
    in a journal of the day: 

If a military or naval officer of the United States, in the necessary suppression of a mutiny or enforcement of obedience, should wound or take the life of a subordinate, would it be contended that, if arrested for that act by the State authority, he could not be released on habeas corpus, because no statute expressly authorized the performance of the act?  If the commander of a revenue cutter should be directed to pursue and retake a vessel which, after seizure, had escaped from the custody of the law, and the officer in the performance of that duty, and when necessary to overcome resistance, should injure or kill a member of the crew of the vessel he was ordered to recapture, and if for that act he should be arrested and accused of crime under the State authority, will any sensible person maintain that the provisions of the habeas corpus act could not be invoked for his release, notwithstanding that no statute could be shown which directly authorized the act for which he was arrested?  If by command of the President a company of troops were marched into this city to protect the subtreasury from threatened pillage, and in so doing life were taken, would not the act of the officer who commanded the troops be an act done in pursuance of the laws of the