Something like Bad Doctor. They could not get rid of a bad surgeon, and in this they could arrest a highly qualified nurse who killed patients in the hospital.
The story is real. She doesn't tell you why he killed. She tells how he was forced to confess what he had done.
The film is well made and we have to pay tribute to the actors: they played well. It was an unfinished story about a good man who found self-assertion in anonymous murders. What made him do that? ... The answer must be found by the viewer.