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Press Release

Waubay Man Sentenced To 30 Years For Murder

For Immediate Release
U.S. Attorney's Office, District of South Dakota

United States Attorney Brendan V. Johnson announced that a Waubay, South Dakota, man convicted of Second Degree Murder and Assault Resulting in Serious Bodily Injury was sentenced on November 25, 2014, by U.S. District Judge Lawrence L. Piersol.

Mario Contreras, age 36, was sentenced to 360 months on each count to run concurrently.  He was also ordered to be on federal supervised release for a period of 5 years after his release.

Contreras was indicted on the charges by a federal grand jury on August 14, 2012.  A jury trial was held on August 1, 2013, and Contreras was convicted of Second Degree Murder and Assault Resulting in Serious Bodily Injury.

The victim was born on December 31, 2009, and was murdered by her father on January 9, 2012, just days after she turned 2 years old.  The victim’s mother and father were never married and were no longer close. The defendant was not very involved in the victims’ first year and a half of her life.  On January 4, 2012, the victim’s mother asked Contreras if he could watch their daughter for a few days.  Contreras had custody of the victim from January 4th through January 9th, the date of death.

Contreras told investigators that on January 9th his daughter was having a cup of water and a banana and he left the room. He said that is when she fell off the chair and sustained the injuries that cased her death.

The Assistant Medical Examiner of Ramsey County, Minnesota, who performed the autopsy, discovered 18 round bluish-colored contusions on four sides of the victim’s head, indicative of blunt force trauma.  He concluded that the multiple contusions and resulting subdural hematoma could not have been caused by a single fall from a chair and that the cause of death was a homicide.  Another government expert on child abuse also concluded that the injuries were inconsistent with falling from a chair or table.  An additional expert for the government determined that there were small hemorrhages to the retinas and concluded that the child was beaten.  Two government experts testified that the chances of such a short fall causing death were “one in a million.”

This case was investigated by the Federal Bureau of Investigation, the Sisseton-Wahpeton Tribal Law Enforcement Services, and the Bureau of Indian Affairs.  The case was prosecuted by Assistant U.S. Attorneys Thomas J. Wright and Jay P. Miller. 

The defendant was remanded to the custody of the U.S. Marshals Service.

Updated June 22, 2015