Fintan Dunne trilogy

It's just another murder, one of the hundreds of simple homicides in 1939: A spinster nurse is killed in her apartment, a suspect is caught with the murder weapon and convicted. Fintan Dunne, the P.I. lured onto the case and coerced by conscience into unraveling the complex setup that has put an innocent man on Death Row, will soon find that this is a murder with tentacles which stretch far beyond the crime scene... to Nazi Germany, in fact, following...