- "Mary Surratt and the Plot To Kill Abraham Lincoln," by Kate Clifford Larson.
http://www.amazon.com/gp/aw/d/0465024416...8&sr=&qid=
Well-written, well-researched, and very informative - IMO it is nearly impossible to believe in Mary Surratt's innocence after reading this book, even the author changed her view in the course of her research:
"She states that even though she went into the project believing in Mrs. Surratt’s innocence, she finished the project feeling very strongly that not only was Mrs. Surratt guilty of the charges, but she was even more involved than what the military tribunal uncovered."
http://thecivilwarproject.com/book-and-m...ccomplice/
(The review nails what I think of the book - much better than I could word it.)
The Assassin’s Accomplice
