In April 1861 Maryland’s legislature voted 53 to 13 against secession but refused to reopen rail links to the North, and on April 19 a Baltimore mob attacked Union troops passing through the city. John Merryman, a Baltimore County planter and militia lieutenant, followed what he believed were state orders and destroyed railroad bridges over the Bush and Gunpowder rivers. Lincoln had authorized General Winfield Scott to suspend habeas corpus along the military route, and on May 25 soldiers arrested Merryman at his home and locked him in Fort McHenry, soon nicknamed the Baltimore Bastille.

His lawyers went straight to Chief Justice Roger B. Taney, sitting as circuit judge, who ordered General George Cadwalader to produce Merryman. Cadwalader sent a colonel with a letter instead, Taney held him in contempt, and the marshal sent to arrest the general was turned away at the gate. Taney’s written ruling argued that the suspension clause sits in Article One and belongs to Congress; Lincoln ignored it and defended his actions to Congress in July. Merryman was indicted for treason, released on $20,000 bail, and never tried, as Taney and later Salmon P. Chase kept postponing the case.

• Federal judge William Fell Giles had already seen one of his writs ignored by the Fort McHenry commander.
• The treason indictment charged Merryman with leading about 500 armed men against federal infrastructure.
• Federal authorities also detained Baltimore Mayor George Brown and Congressman Henry May.
• Editor Frank Key Howard, grandson of Francis Scott Key, was held in the same fort that inspired his grandfather’s anthem.
• Congress passed the Habeas Corpus Suspension Act in 1863, and the same tension resurfaced in Hamdi v. Rumsfeld in 2004.