A Question Of Degree

The woman whose body was found down a South Wales coal mine was a stranger to those parts. She had come from the north-east in search of a missing husband and with the help of an enquiry agent had found him. The police put two and two together and the husband confessed to the crime but at his trial an able defence counsel tore the police evidence to ribbons to the relief of Inspector Crow who had always distrusted the confession. Why had it been made? Crow had to travel to Canada to find the origins of the mystery.