Porcupine Man Sentenced to Eight Years in Federal Prison for Involuntary Manslaughter and False Statement

RAPID CITY - United States Attorney Alison J. Ramsdell announced today that U.S. District Judge Karen E. Schreier has sentenced a Porcupine, South Dakota, man convicted of Involuntary Manslaughter and two counts of False Statement. The sentencing took place on April 25, 2025.

Clayton Fire Thunder, age 40, was sentenced to a total of eight years in federal prison, followed by three years of supervised release. He was also ordered to pay $300 in special assessments to the Federal Crime Victims Fund.

A federal grand jury indicted Fire Thunder in May 2024. He was found guilty following a federal jury trial in Rapid City, South Dakota, in January of 2025.

On the early morning of September 15, 2022, a male drove his partially clothed girlfriend to Indian Health Services (IHS) hospital on the Pine Ridge Reservation and dropped her off at the Emergency Department. The male did not provide his identity nor the female’s identity. The male told medical personnel that a firearm went off while they were engaged in intimate relations and that she had been shot accidentally.

Law enforcement identified and located the male at his residence several hours later. The male was cleaning the crime scene and sent text messages to the female’s relative’s claiming the shooting was an accident. A search of the residence was conducted. Law enforcement was unable to locate the handgun that the male claimed was used in the shooting. The male was arrested and eventually charged with second degree murder, possession of a firearm by a prohibited person and conspiracy to distribute methamphetamine. A digital surveillance system that recorded traffic to the male’s house was seized by law enforcement.

After reviewing the footage, law enforcement identified a vehicle that appeared at the male’s residence shortly after midnight and just before the female was brought to IHS. After several months, law enforcement was able to identify the driver of the vehicle as Marino Waters and the passenger as Clayton Fire Thunder. The investigation revealed that Waters drove Fire Thunder to the male’s residence just east of Pine Ridge two times on the morning of September 15, 2022. Fire Thunder intended on selling a firearm to the male in exchange for cash and/or methamphetamine. The male did not answer the door when Fire Thunder knocked, and unexpectedly, Fire Thunder discharged one round from the firearm into the residence. The round ended up penetrating the siding, backboard, and drywall of the residence and struck and killed the male’s girlfriend, a 27-year-old female.

When Fire Thunder was interviewed by the FBI in March of 2023, he gave a false statement and said that he did not have a firearm when the shooting occurred. Fire Thunder admitted to being at the residence and told law enforcement that he was inquiring with the male homeowner about a junked car at 4:00 o’clock in the morning. Fire Thunder was reinterviewed again in October 2023. Fire Thunder continued to deny that he possessed a firearm during the shooting death of the female and this time said that he was inquiring about a flatbed at 4:00 o’clock.

Seventeen witnesses and over 200 exhibits were introduced at Fire Thunder trial establishing that Fire Thunder possessed and discharged a firearm on the morning of September 15, 2022, that resulted in the death of a 27-year-old female. The jury found Fire Thunder guilty of involuntary manslaughter and two counts of false statement.

This matter was prosecuted by the U.S. Attorney’s Office because the Major Crimes Act, a federal statute, mandates that certain violent crimes alleged to have occurred in Indian country be prosecuted in Federal court as opposed to State court.

This case was investigated by the Oglala Sioux Tribe Department of Public Safety and the FBI. Assistant U.S. Attorney Megan Poppen prosecuted the case.

Fire Thunder was immediately remanded to the custody of the U.S. Marshals Service.