Avenging Lincoln’s Death: The Trial of John Wilkes Booth’s Accomplices is an examination of the 1865 military commission trial of eight alleged accomplices of John Wilkes Booth, the assassin who murdered President Abraham Lincoln. The book analyzes the trial transcript and other relevant evidence relating to the guilt of Booth’s alleged accomplices, as well as a careful application of basic constitutional law principles to the jurisdiction of the military commission and the fundamental fairness of the trial. The author found that the military commission trial was unconstitutional and unfair because Congress never authorized trial by military commission for these eight civilians. President Johnson exceeded the scope of his authority as commander in chief by ordering the accomplices to be tried by military commission. He failed to follow the Habeas Corpus Act of 1863 that required him to turn over the alleged accomplices to civilian authorities for prosecution. The accomplices were convicted on perjured testimony and the Government was allowed to drag in unrelated evidence of Confederate atrocities to poison the minds of the panel of officers.

On July 20, 1864, the Civil War struggle for Atlanta reached a pivotal moment. As William T. Sherman's Union forces came ever nearer the city, the defending Confederate Army of Tennessee replaced its commanding general, removing Joseph E. Johnston and elevating John Bell Hood. This decision stunned and demoralized Confederate troops just when Hood was compelled to take the offensive against the approaching Federals. Attacking northward from Atlanta's defenses, Hood's men struck George H. Thomas's Army of the Cumberland just after it crossed Peach Tree Creek on July 20. Initially taken by surprise, the Federals fought back with spirit and nullified all the advantages the Confederates first enjoyed. As a result, the Federals achieved a remarkable defensive victory. Offering new and definitive interpretations of the battle's place within the Atlanta campaign, Earl J. Hess describes how several Confederate regiments and brigades made a pretense of advancing but then stopped partway to the objective and took cover for the rest of the afternoon on July 20. Hess shows that morale played an unusually important role in determining the outcome at Peach Tree Creek--a soured mood among the Confederates and overwhelming confidence among the Federals spelled disaster for one side and victory for the other.