Alice MacGowan and Perry Newberry. Who Is This Man? (1927) 346 pp.
It is 1921 and Jerry Boyne, private investigator and head of the Bankers Security Agency, has been hired by a young woman, Loyall Tavenar, to accompany her from San Francisco to her childhood hometown (the fictional Monteco in the equally fictional Chagres County) in the Sierra foothill country of California. She has been summoned back home because the man accused of savagely murdering her entire family seven years ago has been captured and is being held in the local jail. Complicating matters is the fact that, at the time of the murders, the accused, Graham Marr, was Loyalls star-crossed lover; the Marrs and Tavenars had been feuding for generations. Although everyone in town positively identifies the prisoner as the fugitive Marr, he steadfastly maintains that his name is actually Alonzo Crede and that he is a Texas cowboy, a veteran of the war in France, and a man with family roots in Pennsylvania. Then, friends and relatives start showing up and confirming the prisoners story, and the town’s residents split into those who believe he is Marr and those who believe he is Crede. Boyne realizes that, in order to determine the mans real identity, he needs to find the answers to several questions about the fateful night of the murders: Why was Marrs horse—which was trained to stay in place when the bridle reins were hanging on the ground—tied up outside the Tavenar rancho? Why was the Chinese cook killed? Was revenge really the motive behind the killings? Why would a man like Gray Marr, who everyone agrees was a stand-up guy, run away instead of facing the consequences of his actions? Once he knows the answers to these questions, Boyne can answer the title question. A note at the end of the novel claims that it is based on an actual case of fivefold killing in a midland California city [that] resulted in … a tangle of identification, in which the whole town was rent asunder in opposing factions.
Setting: Monteco (Chagres County, Calif.); San Francisco 
Baird & Greenwood 1621