A man from Mission, South Dakota, has been sentenced to federal prison after being convicted of assaulting a federal officer. U.S. District Judge Eric C. Schulte sentenced Shannon Dunham, 38, to eight months in federal prison followed by three years of supervised release. Dunham was also ordered to pay a $100 special assessment to the Federal Crime Victims Fund.
Dunham was indicted by a federal grand jury in November 2024 and pleaded guilty on August 7, 2025. The incident leading to his conviction occurred in October 2024 on the Rosebud Sioux Indian Reservation. According to authorities, an officer from the Rosebud Sioux Tribe Law Enforcement Services responded to a disturbance report at a residence in Mission involving Dunham. Upon arrival, the officer encountered Dunham, who became verbally aggressive, grabbed the officer, and brandished a knife before being arrested.
The case was investigated by Rosebud Sioux Tribe Law Enforcement Services and prosecuted by Supervisory Assistant U.S. Attorney Kirk Albertson.
Dunham was immediately remanded into custody of the U.S. Marshals Service following sentencing.
