William M. Moran
- Commanding officer of the Detective Bureau.
Ernest Heath
- Sergeant of the Homicide Bureau.
Snitkin
- Detective of the Homicide Bureau.
Burke
- Detective of the Homicide Bureau.
Captain Anthony P. Jerym
- Bertillon expert.
Captain Dubois
- Finger-print expert.
Dr. Emanuel Doremus
- Medical Examiner.
Dr. Drumm
- An official police surgeon.
Marie O'Brien
- A Police nurse.
Swacker
- Secretary to the District Attorney.
Currie
- Vance's valet.
