What are the elements of the duress defense?

There are three elements of the duress defense: (1) an immediate threat of death or serious bodily injury, (2) a well-grounded fear that the threat will be carried out, and (3) no reasonable opportunity to escape the threatened harm. United States v. Shapiro, 669 F.2d 593, 596 (9th Cir.1982). Sometimes a fourth element is required: the defendant must submit to proper authorities after attaining a position of safety. United States v. Peltier, 693 F.2d 96 (9th Cir.1982) (per curiam).