The Denison Police Department is currently staffed with thirteen sworn full time officers and ten civilian employees. The department is led by Chief Dan Schaffer. Chief Schaffer began his law enforcement career in 1979 serving in municipal law enforcement until 1988 when The joined the Iowa State Patrol. At the time of his retirement from the state patrol, Chief Schaffer had obtained the rank of Lieutenant and had most recently served as a Post Commander stationed out of Mason City, Iowa. The department's patrol staff is comprised of Sgt. Doug Peters, Sgt. Tony Trejo and nine patrol officers. The department also has a K9 program comprised of Officer Chris Jochims and his K9 partner, Piko, a four year old German Shepherd who is trained in narcotics detection.
In addition to providing police protection throughout the city the police department also staffs and manages the 911 Center for the entire county. The Communications Center is the only public service answering point in Crawford County and is responsible for dispatching the Denison, Dow City, Manillla, and Charter Oak police departments, the Crawford County Sheriff's Office, eight fire departments and their respective EMS first responder personnel, and the Crawford County Memorial Hospital EMT/Paramedic Ambulance Service. The Communications Center is staffed by four full-time and five part-time civilian communication operators.