The 421-page volume, 6 1/2 by 9 1/2 inches, "handsomely bound in half calf", was Pitman's book of the conspiracy trial.
Pitman had been appointed "official recorder" of the trial and 10 days before the Military Commission passed sentences (on June 30, 1865), Pitman wrote to Judge Advocate General Brigadier General Jospeh Holt, telling him Cincinnati publishers Moore, Willstach and Baldwin were willing to produce in "respectable book shape" a record of the proceedings. Pitman pointed to his earlier work, , and sought Holt's permission to go ahead with the Lincoln assassination conspiracy trial book. This appeared later in 1865.
Pitman opened his letter with reference to a need "To satisfy the present public desire". His application was approved and endorsed by 11 of the highest-ranking officers in the US Army.
Unfortunately, I can't find online any reference to the 1910 Cincinnati magazine article about Pitman's statement on Surratt's innocence. It is not in The New York Times digital library. There is an interesting post on a site called "Digging Cincinnati History" which contains an obituary for Pitman from the Cincinnati Enquirer of December 29, 1910. But the post is primarily about Pitman's spectacular and heritage-listed house at 1852 Columbia Parkway, East Walnut Hills (above). It does not mention Pitman's "deathbed" defence of Surratt.
However, (Princeton University Press, 2002), edited by Joan E. Cashin, mentions just such a Pitman defence, saying it was made soon after
In a review of Kate Clifford Larson's 2009 book The Assassin's Accomplice: Mary Surratt and the Plot to Kill Abraham Lincoln, Elizabeth D. Leopold began, "The degree of Mary Surratt's complicity in the plot to kill President Abraham Lincoln has been a matter of considerable debate since April 14, 1865."Leopold's review, in The Journal of Military History, said that in Larson's "estimation Surratt was, unequivocally, 'guilty', for she was the woman who 'nurtured and helped cultivate the conspiracy to kill' Lincoln".
Leopold wrote, " ... with regard to primary sources, I would argue that Larson has relied much too heavily (and without any explicit interrogation of their value) on too few items ... In terms of the actual trial testimony, Larson has depended on recorder Benn Pitman's version, which is indeed useful but not without significant flaws Larson should consider and mention: Pitman, for example, summarized, paraphrased, and reorganized much of what he heard in court, rather than writing out the testimony verbatim in chronological question and answer form. In addition, Pitman's version amounted to the Federal government's 'official' account, and thus inevitably reflected the prosecution's biases."