A 19-year-old man from Ethete has been sentenced to 81 months in federal prison for sexually abusing a child on the Wind River Indian Reservation, with a federal judge also ordering him to pay restitution to his victim. Chief U.S. District Court Judge Scott W. Skavdahl handed down the sentence on July 29, which includes five years of supervised release once Tynan LeShawn Addison completes his prison term.
According to FBI Denver, the sentencing stems from a case the agency helped announce alongside the U.S. Attorney's Office for the District of Wyoming. That office's press release, detailed by the U.S. Attorney's Office for the District of Wyoming, fills in the specifics missing from the initial social media post: Addison's full identity, his exact 6.75-year sentence, and a restitution order requiring him to pay $2,105.75 to the victim.
Court records show the underlying assault took place in September 2025. The case came to light after the victim's mother brought her to a medical clinic, where examiners identified physical injuries consistent with a sexual assault, according to the U.S. Attorney's Office. That medical evidence became central to substantiating the report that ultimately led to federal charges.
From Indictment to Guilty Plea
A federal grand jury indicted Addison on November 19, 2025, in a case filed under docket number 25-CR-00162. He pleaded guilty on May 8, roughly two and a half months before Skavdahl imposed the sentence at the federal courthouse in Cheyenne. The Federal Bureau of Investigation conducted the criminal investigation, and Assistant U.S. Attorney Kerry Jacobson prosecuted the case, per the U.S. Attorney's Office.
The case fell under federal jurisdiction because of where it happened. Ethete sits on the 2.2-million-acre Wind River Indian Reservation, home to the Northern Arapaho and Eastern Shoshone tribes, according to the Northern Arapaho Tribe. Under 18 U.S. Code § 1153, known as the Major Crimes Act of 1885, the federal government holds exclusive jurisdiction over major violent crimes, including felony sexual abuse, committed on tribal reservation lands, as explained by Eisner Gorin LLP. That law is why the case was handled in U.S. District Court rather than a state court.
Part of a Larger Federal Push on the Reservation
Addison's sentencing arrives amid sustained federal law enforcement attention on Wind River. In August 2025, federal authorities deployed more than 90 FBI personnel to the reservation as part of a Rocky Mountain Safe Trails Task Force initiative targeting violent crime and drug trafficking, according to Cowboy State Daily. Hoodline previously covered task force sweeps tied to that same enforcement push in the region.
Addison's case is not an isolated one. In August 2024, Skyler Sven Quiver, also of Ethete, was sentenced to 70 months in federal prison for sexual abuse of a person incapable of consent, according to the U.S. Attorney's Office District of Wyoming. And in the same Justice Department release covering Addison's sentence, officials announced that 22-year-old Dakota Fletcher, also of Ethete, was sentenced on August 6 to time served and two years of supervised release for assaulting a Bureau of Indian Affairs law enforcement officer on the reservation.
Together, the cases point to a steady stream of federal prosecutions originating from the small tribal community. The U.S. Attorney's Office for Wyoming and the FBI have repeatedly targeted violent crime, sexual offenses, and drug trafficking on Wind River through multi-agency operations, an ongoing effort that shows no signs of slowing.
