Macnaghten incorrectly described Druitt as a 41-year-old doctor, and cited allegations that he "was sexually insane" without specifying the source or details of the allegations. Macnaghten did not join the force until 1889, after the murder of Kelly and the death of Druitt, and was not involved in the investigation directly. Macnaghten's memorandum named two other suspects ("Kosminski" and Michael Ostrog) and was written to refute allegations against a fourth, Thomas Cutbush. The three Macnaghten suspects — Druitt, Kosminski and Ostrog — also match the descriptions of three unnamed suspects in Major Arthur Griffiths' "Mysteries of Police and Crime" (1898); Griffiths was Inspector of Prisons at the time of the Ripper murders.