Where was John Surratt on April 14, 1865 ?

[Gene C]

Is it feasible to think that many people held John Surratt somewhat responsible for Mary's imprisonment and death sentence, as he seemed to show more concern for his own survival that that of his mother? Knowing that he was involved with Booth, his involvement as a confederate courier, Booth's visits to the boarding house the day of the assassination, cast a large and dark shadow on his mother.

Claims that John was seen in Washington on the day of the assassination ties him closer to Booth and his plot. Convinced of his guilt and involvement in Lincoln's assassination, whether it is true or not that John was in Washington, it maybe the only act of retribution Atzerodt (and others) can do to make things more difficult for John, and to ensure he is punished for the perceived greater sin of deserting his mother in her time of peril.