Unfortunately I’ve not been very cautious and I overlooked the following post at In Search of the Classic Mystery Novel: The Fatal Pool by John Rhode.
His final verdict was: Not Recommended.
I will choose to read then an earlier book in the series In Face of the Verdict (1936) (U.S. title In the Face of the Verdict).
Book Description: In Face of the Verdict, first published in 1936, is book no. 24 in the series of mysteries featuring private detective Dr. Priestley. Author John Rhode, a pen name of Cecil Street (1884-1964), was a prolific writer of mostly detective novels, publishing more than 140 books between 1924 and 1961. In Face of the Verdict, Dr. Priestley is called to the harbor town of Blacksand to find the killer of two brothers, both of whom died by drowning.