In Washington on June 14, the last witness testified in the military trial of the eight people — Mary Surratt, Lewis Powell, George Atzerodt, David Herold, Samuel Mudd, Edman Spangler, Samuel Arnold and Michael O’Laughlen — implicated in the assassination of Abraham Lincoln and the attempted murder of Secretary of State William Seward on April 14.
Arguments of counsel began; for the government, John A. Bingham summed up in a speech that lasted six days. The summations of both sides took two weeks, and on June 30, the military commission found all eight guilty as accused.
The trial had lasted 50 days and the commission had heard testimony from 366 witnesses; the trial transcript ran to 4,900 pages. The findings were submitted later that day to President Andrew Johnson by Judge Advocate Joseph Holt, and on Wednesday, July 5, the president approved the findings of the court.
It was later revealed that five of the nine men on the commission had been against the death sentence for a woman — these were Victorian times and womanhood was revered — and had sent to President Johnson with the verdicts a vote for clemency that her sentence been changed to life imprisonment. Johnson later loudly protested that he had never seen the request for clemency, and blamed Judge Advocate Holt for withholding it. The president therefore approved the findings of the court.
On Thursday, July 6, the prisoners were informed of the verdicts and sentences: Mary Surratt, Lewis Powell, David Herold and George Atzerodt were to be hanged the following day in the courtyard outside the prison at the Washington Arsenal, between the hours of 11 a.m. and 1 p.m. Samuel Arnold, Michael O’Laughlen and Samuel Mudd were sentenced to life imprisonment at the federal prison in Albany, N.Y.
Edman Spangler was sentenced to six years in the federal prison in Albany. Public shock and disbelief met the news of Mary Surratt’s sentence, and there was a public outcry for clemency. Her daughter, Annie, made an attempt to see President Johnson at the White House and plead for mercy. Her pitiful cries could be heard all through the house when she was prevented from seeing Johnson by two Radical Republicans, Sen. Preston King of New York and Sen. James Lane of Kansas.
The verdicts had been sent by telegraph to the country, and the trains headed to Washington that day were jammed with the curious and the morbid. That night and the next morning, at the arsenal penitentiary, the gallows were built, and the traps and nooses tested.
Friday, July 7, was an unbearably hot and humid day in Washington. The temperature was well into the 90s by noon. At a little after 1 p.m., the condemned were led out of the prison assisted by spiritual counsel and armed guards. It was reported that the heavily-veiled Mary Surratt nearly fainted when she caught sight of the gallows in front of her, and the four fresh graves and coffins to the right of the gallows.
When she had climbed the steps to her chair behind the trap, she was heard to say, “Please don’t let me fall.” Maj. Gen. John Hartranft, in charge of the arsenal prison, read the findings of the court and the sentences. When Capt. Christian Rath, in charge of the execution party, was told to proceed, he exclaimed in dismay, “Her, too?!”
By 2 p.m., it was over; three men and one woman hung lifeless under the blazing sun and in the oppressive heat. Shortly the bodies were taken down and the jail physician stepped up to examine them, and declared them dead. The bodies were placed in the coffins; each had a bottle containing a note with the name of the deceased. They were buried in the graves next to the gallows.