In 1908 Marion Cilchrist was murdered in her home; a rather unlikable woman but white, Christian, wealthy, and elderly, so the crime must be solved with the utmost speed - accuracy be damned.
With very little investigating actually going on, the police set their sights on Oscar Slater. Slater was an immigrant and Jewish, so naturally the prime suspect. The book is really commentary on the bigotry of the times (which we know still exists today), and there are many layers to the story on top of it being an excellent historical true crime drama. Slater was the perfect suspect - he made a living as a gambler who lived with a prostitute and may himself run some sort of brothel (which he denied). The one piece of evidence the police had against him was a pawn ticket for a brooch that somewhat matched the description of one stolen from Gilchrist's home during her murder. Slight problem - the pawn ticket was written up a few weeks before the murder. But never mind actual facts; the police continued on their way, railroading Slater by coaching witnesses to identify him, despite the fact he did not remotely fit the descriptions given of the man seen lingering around Gilchrist's home. Even though Slater was clearly innocent, he was found guilty and sentenced to death. A stay of execution was granted and instead Slater found himself on his way to Peterhead Prison for a life of hard labor.
Arthur Conan Doyle took great interest in the case, unsurprisingly but did not actually become involved in solving it until he received a smuggled message from Slater in 1925 - by then Slater had been in prison for nearly twenty years. Still, Conan Doyle saw the gross miscarriage of justice and got to work right away, using the very same methods as his famous protagonist to attempt to solve the murder - and if not solve it, then at least prove Slater's innocence. Conan Doyle was relentless in his pursuit, pouring over every last bit of documentation he could get his hands on - trial transcripts, witness statements, even newspaper accounts. He worked tirelessly to note all the inconsistencies he found, and there were plenty. In the end, he was finally able to win Slater his freedom and the man was released in 1927.
The social commentary here is just a crucial as the crime and trial, because they are wholly intertwined. Slater was a German immigrant and Jewish, so he was someone to be feared. No matter that he was well-traveled and spoke English well, he was still of a lower class and thus had to be a criminal. Even Slater's champion had a rather low opinion of him to start with, referring to him as a blackguard at one point. Even so, Conan Doyle was also a champion of justice reform and his work is the only reason Slater saw freedom once again. Unfortunately Slater did not seem terribly grateful to Conan Doyle and a very public spat made him all the more unsympathetic, even to those who recognized he was innocent, after Conan Doyle's hard work in getting Slater's sentence overturned.
This is an engaging read that I could not put down. Highly recommended.