United States Attorney Ron Parsons announced on July 14 that Jonathan Sierra, a 22-year-old man from Parmelee, South Dakota, was sentenced for assaulting, resisting, and impeding a federal officer. U.S. District Judge Eric C. Schulte handed down the sentence on July 6 in Pierre.
Sierra received a sentence of time served through August 7, 2026—equal to approximately ten months in custody—followed by three years of supervised release. He was also ordered to pay a $100 special assessment to the Federal Crime Victims Fund.
According to the announcement, Sierra was indicted by a federal grand jury in January 2026 and pleaded guilty on April 1, 2026. The conviction is related to an incident that took place in July 2025 within the Rosebud Sioux Indian Reservation. During the incident, a Rosebud Sioux Tribe Law Enforcement Services Officer was speaking with Sierra’s ex-girlfriend at her residence in Mission when Sierra arrived at the house. After being asked by the officer to exit his vehicle, Sierra did so while holding a knife. The officer repeatedly commanded him to put down the knife; eventually, Sierra threw it into the street. When officers attempted to detain him, he struggled and kicked both responding officers.
The case was investigated by Rosebud Sioux Tribe Law Enforcement Services and prosecuted by Assistant U.S. Attorney Kimberly Zachrison. Following sentencing, Sierra was immediately remanded into custody of the U.S. Marshals Service.
The U.S. Attorney for the District of South Dakota serves as chief federal law enforcement officer for its district and handles both criminal prosecutions and civil cases across all of South Dakota; it also supports initiatives aimed at improving public safety and quality of life throughout its jurisdiction, according to the official website.