JOHNSON CITY, TN (WJHL) – A man who Johnson City police said used a steak knife to kill his grandmother back in 2011 will spend more than a decade behind bars for the crime.

Cody Russell pleaded guilty to second-degree murder today in Washington County Criminal Court.

Investigators originally charged him with first-degree murder after he attacked his grandparents inside their Stoneybrook Heights apartment in December 2011. His grandmother Frieda Russell died in that attack. His grandfather survived despite police saying Russell slashed the man’s throat with a butcher knife.

Judge Lisa Rice sentenced Russell to a 15-year prison sentence this morning and ruled he’ll have to serve every day of that sentence. Since he’s remained in jail for the last three-and-a-half years Russell will receive credit for time served.Copyright WJHL 2015. All rights reserved.