[hillsboroughman]

The modern cop novel was a formula popularized in England by Edgar Wallace already in the 1915-20 timeframe. His novels show great command of police procedure incl crime scene analysis, lab work, post mortem, ballistics, finger printing etc.. He is said to have written some 170 novels, not all of them were police thrillers. Later in life, he went to Hollywood and wrote screenplays.

I guess his earlier work is not very well-known in the US.

Just my 2c