Alison J. Ramsdell U.S. Attorney | U.S. Attorney for the District of South Dakota
A South Dakota man has been sentenced to 18 months in federal prison for failing to register as a sex offender. The sentence was handed down by U.S. District Judge Karen E. Schrier on February 24, 2025.
Sonny Gray Grass, aged 63, will serve one year and six months in prison, followed by five years of supervised release. He has also been ordered to pay a $100 special assessment to the Federal Crime Victims Fund.
Gray Grass was indicted in November 2024 by a federal grand jury for failing to register as a sex offender and pleaded guilty in December of the same year. His previous conviction dates back to September 9, 2013, when he was found guilty of abusive sexual contact in the U.S. District Court for the District of South Dakota. This required him to register under the Sex Offender Registration and Notification Act, which he failed to do while residing in Sioux Falls in August 2024.
The case is part of Project Safe Childhood, an initiative launched by the Department of Justice in May 2006 aimed at combating child sexual exploitation and abuse. The project coordinates efforts from federal, state, and local resources to prosecute offenders and rescue victims.
The investigation was conducted by the U.S. Marshals Service, with Assistant U.S. Attorney Connie Larson leading the prosecution.
Following his sentencing, Gray Grass was taken into custody by the U.S. Marshals Service.
