John Merryman, a state legislator from Maryland, is arrested for attempting to hinder Union troops from moving from Baltimore to Washington during the Civil War and is held at Fort McHenry by Union military officials. His attorney immediately sought a writ of habeas corpus so that a federal court could examine the charges. However, President Abraham Lincoln decided to suspend the right of habeas corpus, and the general in command of Fort McHenry refused to turn Merryman over to the authorities.
Federal judge Roger Taney, the chief justice of the Supreme Court (and also the author of the infamous Dred Scott decision), issued a ruling that President Lincoln did not have the authority to suspend habeas corpus. Lincoln didn't respond, appeal, or order the release of Merryman. But during a July 4 speech, Lincoln was defiant, insisting that he needed to suspend the rules in order to put down the rebellion in the South.
Five years later, a new Supreme Court essentially backed Justice Taney's ruling: In an unrelated case, the court held that only Congress could suspend habeas corpus and that civilians were not subject to military courts, even in times of war.
This was not the first or last time that the U.S. federal government willfully ignored its own laws during times of strife. Hundreds of thousands of Japanese Americans were sent to internment camps following the attack on Pearl Harbor and America's entry into World War II. Some forty years later, a U.S. congressional commission determined that those held in the camps had been victims of discrimination. Each camp survivor was awarded $20,000 in compensation from the U.S. government.