In 1937, the District 4 office was located at Fifth Avenue South and 16th Street in Denison and was originally known as District 3. It consisted of Carroll, Crawford, Ida, Monona, Sac, and Woodbury counties.  The first commanding officer for this District was Sergeant Everett Martin.  

When new districts were established in 1946, the present District 4 was formed.  It currently consists of Audubon, Carroll, Crawford, Greene, Guthrie, Harrison, Monona and Shelby counties, with the District Headquarters residing in Denison. 

In 1990, the 74th Iowa General Assembly provided funding for the purchase of a pre-existing facility as the new headquarters for District 4.  This building is located on the east edge of Denison on Highway 30.  The building also has offices for the Department of Narcotics Enforcement (DNE) and State Fire Marshal (SFM) Divisions.

Over the years District 4, in addition to District 3, has responded to some of Iowa’s most devastating events, including the Floods of 2008 and The Little Sioux Boy Scout Ranch Tornado which killed four and injured 48.  District 4 personnel were also dispatched to eastern Iowa to assist with the historical flooding in Cedar Rapids.  District 4 personnel assisted with the response of the United Airlines Flight 232 crash in Sioux City in July 1989.  Security was provided during Russian Party Chairman Nikita Khrushchev’s visit to the Garst Seed Farms in Coon Rapids in September of 1959.  The troopers of District 4 assist at regularly scheduled events such as R.A.G.B.R.A.I., Iowa State University football games, Farm Progress Show and various small town summer celebrations and parades.

To date, only one trooper was killed while serving in District 4. On July 2, 1955, Trooper Ralph Garthwaite was killed in the line of duty by an intoxicated driver in a near-head on collision south of Dunlap. Two other officers from the district have had harrowing experiences while performing their duties.

In 1945, John Mahnke was kidnapped while patrolling in Crawford County. Mahnke was left chained to a furnace in a country school house in northern Iowa.

In January 1967, Donald Jenkins was wounded while trying to apprehend a suspect to investigate the passing of bad checks. He chased the suspects until their car spun out. As the patrolman stepped from his patrol car, they opened fire, hitting Jenkins in the leg twice.  One bullet shattered his leg. The three men were later apprehended by Lieutenant Austin Keller about seven miles from the scene of the shooting.

Iowa State Patrol District #4
3710 Hwy 30 E
Denison IA 51442