In Green v. United States, 355 U.S. 184 (1957), the defendant was indicted on one count of arson and one count of first degree murder by causing the death of a person in perpetrating the arson, an offense that is commonly referred to as felony murder. 355 U.S. at 185. At the conclusion of the evidence, the trial judge instructed the jury that it could find Green guilty of arson under the first count and of either first degree murder or the lesser-included offense of second degree murder. Id. The jury returned a verdict finding Green guilty of arson and second degree murder, but the jury was silent on the charge of first degree murder. Id. at 186. When Green succeeded in having the second degree murder conviction reversed on appeal, he was retried and convicted of first degree murder under the original indictment. Id. The Supreme Court held that the second trial violated the Fifth Amendment prohibition against being twice tried for the same offense: Green was in direct peril of being convicted and punished for first degree murder at his first trial. He was forced to run the gantlet once on that charge and the jury refused to convict him. When given the choice between finding him guilty of either first or second degree murder it chose the latter. In this situation the great majority of the cases in this country have regarded the jury's verdict as an implicit acquittal on the charge of first degree murder. 355 U.S. at 190. In addition to determining that the jury's silence on the first degree murder charge was tantamount to an implied acquittal, the Supreme Court more broadly relied on the "established principle of former jeopardy" that applies when a jury is "given a full opportunity to return a verdict and no extraordinary circumstances appeared which prevented it from doing so" to hold that Green's jeopardy on the charge of first degree murder ended when the jury was discharged following the first trial. Id. at 191. In Green v. United States, the jury was instructed that it could find the defendant guilty of either first-degree or second-degree murder. Id. at 185. The jury found the defendant guilty of second-degree murder but was silent as to first-degree murder. Id. at 186. After the defendant's conviction for second-degree murder was reversed, he was tried again for first-degree murder and raised the defense of double jeopardy. Id. The Court concluded, "A defendant is placed in jeopardy once he is put to trial before a jury so that if the jury is discharged without his consent he cannot be tried again." Id. at 188. The Court also observed that jeopardy does not terminate when "'unforeseeable circumstances . . . such as the failure of a jury to agree on a verdict'" make completion of a trial impossible. Id. In Green, the defendant was tried for first-degree felony murder and convicted of second-degree murder. 355 U.S. at 185-86. There, the government contended that, because second-degree murder was not a proper lesser-included offense of felony murder, the defendant had not been impliedly acquitted of the greater charge. Id. at 194 n.14. The Court disagreed and stated, "It is immaterial to the double jeopardy analysis whether second degree murder is a lesser offense included in a charge of felony murder or not." Id. The Supreme Court inferred that there was an acquittal on a greater offense after the jury returned a guilty verdict on a lesser charge and was silent as to its verdict on the greater offense. The Court considered the jury's silence to be significant because it was possible that the jury had unanimously acquitted the defendant of that charge. Moreover, the Court was sensitive to the hardship that retrial on the higher degree of a crime would place on a defendant's right to appeal: "Reduced to plain terms, the Government contends that in order to secure the reversal of an erroneous conviction of one offense, a defendant must surrender his valid defense of former jeopardy not only on that offense but also on a different offense for which he was not convicted and which was not involved in his appeal" (Green, 355 US at 193).