The case was frequently invoked in the unsuccessful attempt to pass the Wagner-Costigan Act during the presidency of Franklin Roosevelt, which would have made it a federal crime for law enforcement officials to refuse to try to prevent a lynching.
[2] In September 1925, Gunn was convicted of the attempted rape of a student at what is now Northwest Missouri State University, after accosting the young woman on a rural lane outside of Maryville.
[3] On December 16, 1930, a 20-year-old teacher, Velma Colter, daughter of a local farmer, was murdered in the one-room Garrett schoolhouse, (40°19′56.22″N 94°54′40.05″W / 40.3322833°N 94.9111250°W / 40.3322833; -94.9111250) a mile southwest of Maryville.
They found her partly undressed body in a pool of blood inside the school; a bloody footprint left by her killer was on the floor.
[3] Gunn finally confessed, saying he had entered the school with a hedge club after seeing the teacher outside with a coal bucket.
Her oldest son, Floyd Colter, had been killed in France during World War I. Gunn's court date was set for January 12.
The Nodaway County prosecuting attorney insisted Gunn would get a fair trial and appealed (along with Maryville business leaders) to Missouri's governor, Henry S. Caulfield, to deploy the National Guard to prevent an anticipated lynching attempt.
Caulfield complied and 60 guardsmen were ordered at 7:30 a.m. to stand by at the National Guard a block north of the courthouse (today's Maryville Public Library).
By this point a large crowd occupied the Maryville square, between the jail block to the northeast and the Nodaway County, Missouri courthouse.
Gunn was taken inside the schoolhouse, where he is reported to have confessed his guilt again, claiming he had an accomplice named "Shike" Smith.
The mob leader, identified only as the "man in a red coat", threw a lighted piece of paper into the building.
Ironically, he did not back the proposed Wagner-Costigan Act, though he did add a Civil Rights Section to the Justice Department.