Alison J. Ramsdell U.S. Attorney | U.S. Attorney for the District of South Dakota
Alison J. Ramsdell U.S. Attorney | U.S. Attorney for the District of South Dakota
A Sioux Falls man has been sentenced to nearly three years in federal prison for failing to register as a sex offender. The sentencing of Adrian Fast Dog, 45, was announced by United States Attorney Alison J. Ramsdell and took place on July 7, 2025, under U.S. District Judge Roberto A. Lange.
Fast Dog received a sentence of two years and nine months in federal prison, followed by five years of supervised release. He was also ordered to pay a $100 special assessment to the Federal Crime Victims Fund.
The case against Fast Dog began with an indictment by a federal grand jury in June 2024. He entered a guilty plea on April 10, 2025. His conviction is based on his failure to register as a sex offender between June 25, 2024, and February 13, 2025, as required by federal law due to a previous sex offense conviction.
The investigation was conducted by the United States Marshals Service and prosecuted by Assistant U.S. Attorney Ann M. Hoffman.
This prosecution is part of Project Safe Childhood, an initiative launched in May 2006 by the Department of Justice aimed at combating child sexual exploitation and abuse. The project coordinates efforts among federal, state, and local resources to apprehend offenders and rescue victims.
Following his sentencing, Fast Dog was taken into custody by the U.S. Marshals Service.
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