In 1863, the Supreme Court heard the "Prize Cases", which arose after Union ships blockading the Confederacy seized ships that conducted trade with Confederate ports. An adverse Supreme Court decision would strike a major blow against Lincoln's prosecution of the war, since the blockade cut off the crucial Confederate cotton trade with European countries. The Court's majority opinion, written by Associate Justice Grier, upheld the seizures and ruled that the president had the authority to impose a blockade without a congressional declaration of war. Taney joined a dissenting opinion written by Associate Justice Samuel Nelson, who argued that Lincoln had overstepped his authority by ordering a blockade without the express consent of Congress.