The Iowa Supreme Court ruled Friday that Yvette Louisell, a former ISU student who was convicted of first-degree murder in 1987, must be resentenced to life in prison with the possibility of parole.  

The ruling overturns District Court Judge James Ellefson sentencing of 25 years in prison for Louisell in February 2014. If Ellefson’s decision had been upheld, Louisell would have been on track to be released because she has already served over 25 years.

Louisell was 17 years old when a jury convicted her of first-degree murder, stemming from the 1987 stabbing death of Keith Stilwell, a budget analyst at the National Animal Disease Lab in Ames. 

In 2010, the U.S. Supreme Court ruled life sentences without parole to be unconstitutional for people under the age of 18 who have been convicted of murder.

Following the U.S. Supreme Court ruling, District Court Judge James Ellefson sentenced Louisell to 25 years in February 2014. 

The Iowa Supreme Court overruled that sentence Friday, saying the district court did not have the authority to sentence Louisell to a determinate term of 25 years for murder in the first degree. 

Louisell is currently incarcerated at the Iowa Correctional Institution for Women in Mitchellville, Iowa.