HELENA — Two people charged in the 2019 beating and stabbing death of a Helena man have reached plea agreements with Lewis and Clark County prosecutors just weeks ahead of their trials.
Dewayne William Johnson pleaded guilty but mentally ill to mitigated deliberate homicide in the death of Shane White, 56. Prosecutors are recommending a sentence of 30 years in a Department of Public Health and Human Services facility with 20 years suspended.
Serena Kilseimer pleaded guilty on Jan. 6 to a reduced charge of mitigated deliberate homicide in exchange for a recommended 30-year prison sentence with 20 years suspended, the Independent Record reported.
Investigators identified the suspects after images of them with White were captured on security cameras on Sept. 8, 2019 — the day of the killing, court records said.
Johnson was wearing a GPS ankle monitor from another criminal case that allowed him to be tracked to the Cave Gulch area near Canyon Ferry Reservoir, where White’s body was later found.
Johnson was arrested at White’s residence on Sept. 9 on a warrant for falling behind on payments and failing to keep his ankle monitor charged. Kilseimer was present and when asked about White’s whereabouts, she said: “’I’m not talking about any murders,’” court records show.
White’s family reported him missing on Sept. 16. Two days later, his body was found on the family’s property near Cave Gulch.
District Judge Michael McMahon isn’t required to honor the plea agreements and could hand down a longer sentence on Feb. 23, but Johnson and Kilseimer could then withdraw their guilty pleas.
Johnson said he killed White in self-defense after White threatened him, Kilseimer and their child, court records said.