United States Attorney Alison J. Ramsdell has announced the sentencing of Daryl John Plumman, a resident of Parmelee, South Dakota. U.S. District Judge Eric C. Schulte sentenced Plumman to four years and nine months in federal prison for Assault with a Dangerous Weapon and Possession of a Firearm by a Prohibited Person. The sentence includes three years of supervised release and a $200 special assessment to the Federal Crime Victims Fund.
Plumman, 32, was indicted by a federal grand jury in September 2023 and pleaded guilty on July 24, 2024. His convictions relate to two incidents from 2023 on the Rosebud Sioux Indian Reservation.
On April 21, 2023, authorities sought Plumman in connection with an alleged assault earlier that day. He was found in Parmelee sitting in the driver's seat of a parked vehicle with a loaded 9 mm pistol under his seat. Due to a previous conviction for Abusive Sexual Contact in federal court, it is illegal for Plumman to possess firearms or ammunition.
Later, on July 29, 2023, while incarcerated at the Rosebud Sioux Tribe Adult Correctional Facility, Plumman and another inmate assaulted a fellow prisoner using a pencil.
The case fell under federal jurisdiction as mandated by the Major Crimes Act because it involved violent crimes alleged to have occurred in Indian Country. The U.S. Attorney’s Office prosecuted the case.
The investigation was conducted by the Rosebud Sioux Tribe Law Enforcement Services and the Bureau of Alcohol, Tobacco, Firearms and Explosives. Assistant U.S. Attorneys Kirk Albertson and Brian Murphy led the prosecution efforts.
Following his sentencing, Plumman was remanded into custody by the U.S. Marshals Service.