The Supreme Court upheld the conviction of a Japanese-American citizen for violating a Civilian Exclusion Order during World War II. The Court found that the exclusion of Japanese Americans from the West Coast was necessary due to the presence of potentially disloyal members within the group. The Court rejected the argument that the exclusion was based on group punishment and deemed it a military imperative. The Court cannot rule on the lawfulness of the detention program in both assembly and relocation centers since the trial only dealt with the petitioner's violation of the exclusion order. The court will decide the constitutional issues when an assembly or relocation order is applied or is certain to be applied to the petitioner, and the court has its terms before them.

Justice Frankfurter agrees with the Court's decision that Korematsu's actions were criminal under Civilian Exclusion Order No. 34. He believes that the military order was supported by legal considerations in Hirabayashi v. United States and that General DeWitt's orders were clear and not contradictory. Frankfurter asserts that the Constitution grants Congress and the President powers to wage war, and actions taken under the war power must be judged in the context of war. Military orders are not lawless simply because they would be in times of peace. Military authorities are bound by the Constitution, and if a military order is an allowable judgment of war, it is constitutional. Congress has the power to enforce valid military orders by making their violation an offense triable in civil courts. However, recognizing the constitutionality of military measures does not necessarily imply approval of them. It is important to note that if a lower court errs, it must be corrected.

The case involves the conviction of a US citizen of Japanese ancestry for not submitting to imprisonment in a concentration camp solely based on their race, without any inquiry into their loyalty to the United States. The petitioner was charged under a law that made it a misdemeanor to enter, remain in, leave, or commit any act in any military area or zone contrary to the restrictions applicable to that area or zone or contrary to the order of any military commander. The petitioner's Constitutional rights were violated, and the government's argument and the majority opinion erroneously divide the issue. The conflicting orders were a trap designed to lock him up in a concentration camp. The judgment of conviction should be reversed.

The lower court erred in approving the exclusion of all persons of Japanese ancestry from the Pacific Coast area without martial law. Military claims must be subject to judicial review to determine their reasonableness. The exclusion order is unconstitutional and racist, depriving those affected of equal protection under the law and their constitutional rights. The order lacks a reasonable relation to the removal of dangers posed by invasion, sabotage, and espionage. The forced exclusion was based on an erroneous assumption of racial guilt rather than bona fide military necessity. The Commanding General's Final Report failed to show that individuals of Japanese descent posed a special threat to defense installations or war industries. Therefore, the forced exclusion of individuals of Japanese ancestry was not justified and lacked a reasonable relation to the removal of dangers.

The dissenting opinion in the Korematsu case argues that military orders criminalizing presence in a particular area based solely on race and ancestry are unconstitutional. The argument suggests that guilt should be personal and not based on inheritable qualities. Military orders cannot be expected to adhere to traditional tests of constitutionality in areas of probable operations. While the Constitution cannot limit military expedients, it should not be distorted to approve all that the military deems expedient. The Court's acceptance of General DeWitt's untested statement that his orders were reasonable illustrates the limitation of courts in examining the necessity for a military order. Military decisions are not subject to judicial review as they are based on confidential information that cannot be disclosed to courts without risking national security. The danger to liberty from the Army program for deporting and detaining citizens of Japanese extraction is not as subtle as the judicial construction of the due process clause that will sustain this order. The Court's opinion in this case validates the principle of racial discrimination in criminal procedure and of transplanting American citizens, creating a generative power of its own. The author would reverse the judgment and discharge the prisoner.