Maurice Dinwiddie
- Assistant District Attorney.
Chief Inspector O'Brien
- Of the Police Department of New York City.
William M. Moran
- Commanding Officer of the Detective Bureau.
Ernest Heath
- Sergeant of the Homicide Bureau.
Burke
- Detective of the Homicide Bureau.
Snitkin
- Detective of the Homicide Bureau.
Emery
- Detective of the Homicide Bureau.
Ben Hanlon
- Commanding Officer of Detectives assigned to District Attorney's office.
Phelps
- Detective assigned to District Attorney's office.
Tracy
- Detective assigned to District Attorney's office.
Springer
- Detective assigned to District Attorney's office.
Higginbotham
- Detective assigned to District Attorney's office.
Captain Carl Hagedorn
- Fire-arms expert.
Dr. Doremus
- Medical Examiner.
Francis Swacker
- Secretary to the District Attorney.
Currie
- Vance's valet.
