Dell Shannon 
In the Death of a Man [EPUB ebook] 

Jesse Falkenstein was just putting away his notes at the end of the day when he was visited by Mrs Lester, an acquaintance of his sister, who came to him claiming her husband, Glen, had been seen frequently dining with another woman. Jesse was loath to get involved, even though Mrs Lester was his sister’s friend. That was, until he received a phone call from her at police headquarters. ‘They say homicide, my darling Glen!’ Murder was something Jesse did know about, if it was murder . . . ‘My favourite American crime-writer’ New York Herald Tribune