The United States Supreme Court has held that the New York murder statute does not deprive a defendant of due process by placing on him the burden of proving the affirmative defense of extreme emotional disturbance since the defense does not serve to negate an element of the crime.
Patterson v. New York, 432 U.S. 197.(1977).
Anthony J. Krastek,
Constitutional Criminal Procedure - Due Process - Burden of Proof - Affirmative Defenses,
Duq. L. Rev.
Available at: https://dsc.duq.edu/dlr/vol16/iss3/12