Patrolman Ralph Garthwaite was killed when his patrol car was struck head-on by a drunk driver on Highway 30. The incident occurred on a bridge as Patrolman Garhwaite travelled northbound towards Dunlap, Iowa.

The suspect was charged with manslaughter. A jury found him innocent November 30, 1956.

Patrolman Garthwaite had served with the Iowa State Patrol for three years.