Jefferson Davis's Imprisonment

On February 15, 1869, the charges of treason against Jefferson Davis were dropped. From the article:

"Jefferson Davis's Imprisonment

Davis spent two years as a military prisoner at Fort Monroe near Norfolk. Confined to a small room known as a casemate, he was monitored by soldiers who ensured that he ate, made no escape attempt, and did not commit suicide. Later, Davis was moved to spacious quarters in the officers' hall and was allowed visitors and exercise. In May 1866, his wife, Varina Howell Davis, took up permanent residence at Fort Monroe. Although an unauthorized biography suggested that Davis was treated poorly, Davis himself did not believe that to be the case. He was transferred to civilian custody on May 13, 1867, and then released on $100,000 bail.
Americans were divided on how or whether to punish Davis. The government could prosecute Davis for alleged participation in the Lincoln assassination, for the mistreatment of Union prisoners of war, or for leading a rebellion against the United States. U.S. president Andrew Johnson favored murder charges. Many abolitionists and lawmakers opposed punishing Davis, and instead preferred a Reconstruction plan that would punish the former Confederacy. Yet many civilians wrote the president asking for Davis to be hanged; some even volunteered to construct the gallows. The Davis issue remained prominent in public discussion in 1865 until it gave way to other Reconstruction issues, such as the rights of black freedmen. When the Lincoln conspirators' trial failed to establish a connection to Davis, Johnson settled on treason charges.

The government charged Davis with treason against the United States for organizing and arming the 1864 military invasions of Maryland and the District of Columbia during the American Civil War (1861–1865). The defendant demanded a trial as the best forum for proving the constitutionality of secession, and the government requested numerous delays to prepare its case. Although the indictment was finished in March 1868, the Johnson impeachment further delayed the case. The court finally heard preliminary motions in December 1868, when the defense asked for a dismissal claiming that the Fourteenth Amendment to the U.S. Constitution already punished Davis by preventing him from holding public office in the future and that further prosecution and punishment would violate the double jeopardy restriction of the Fifth Amendment. The court divided in its official opinion and certified the question to the United States Supreme Court. Fearing the court would rule in favor of Davis, Johnson released an amnesty proclamation on December 25, 1868, issuing a pardon to all persons who had participated in the rebellion.
After enduring two years of imprisonment and nearly four years of uncertainty, Davis became a free man. The incomplete prosecution of his case and others' gave clear indication that the government intended Reconstruction to realign southern society rather than punish a select few leaders for causing the rebellion.

Time Line
May 10, 1865 - Confederate president Jefferson Davis is captured by Union forces near Irwinville, Georgia.
May 22, 1865–May 13, 1867 - Former Confederate president Jefferson Davis is incarcerated at Fort Monroe following the Civil War. Part of his bail is posted by the abolitionist Horace Greeley.
October 1865 - While incarcerated at Fort Monroe, former Confederate president Jefferson Davis is transferred from a small room called a casemate to more spacious quarters in the officers' hall.
May 1866 - Varina Howell Davis takes up residence at Fort Monroe, where her husband, former Confederate president Jefferson Davis, is imprisoned.
May 13, 1867 - A bail bond of $100,000 for Jefferson Davis is posted and accepted; among those signing the bond are Cornelius Vanderbilt, Horace Greeley, and Gerrit Smith, the radical abolitionist who helped to fund John Brown in 1859. Davis is released and the indictments for treason are dismissed.
March 4, 1868 - The U.S. government files in federal court its final indictment against former Confederate president Jefferson Davis on charges of treason. The trial is further delayed because of the impeachment of President Andrew Johnson.
July 9, 1868 - The Fourteenth Amendment to the U.S. Constitution is ratified. It grants citizenship to all African Americans and bars former Confederate officials from holding state or federal political office. A two-thirds vote by both houses will override that limitation in the cases of Robert E. Lee (1975) and Jefferson Davis (1978).
December 3, 1868 - During his treason trial, former Confederate president Jefferson Davis claims that, should he be found guilty, the Fourteenth Amendment to the U.S. Constitution would punish him a second time by restricting his citizenship rights. He claims that the government is violating the Fifth Amendment's double jeopardy restriction.
December 25, 1868 - President Andrew Johnson's Fourth Amnesty Proclamation absolves former Confederate president Jefferson Davis of any guilt for participation in the Civil War.
February 15, 1869 - U.S. Attorney enters "nolle prosequi" into the record for United States v. Jefferson Davis, thus ending the case."