Kenneth Simpson, a 38-year-old Missouri man, was convicted by a jury on January 24, 2026, of first-degree murder for killing Hermann Police Detective Sergeant Mason Griffith and first-degree assault for wounding Officer Adam Sullentrup during a March 12, 2023, confrontation at a Casey’s convenience store. Simpson now faces either life without parole or the death penalty, with the penalty phase of his trial ongoing as of late January 2026, featuring emotional testimony from victims’ families and colleagues.​
Incident Details
Griffith and Sullentrup responded to reports of an irate individual—later identified as Simpson, who had active warrants—without drawing weapons initially. Surveillance footage captured Simpson suddenly drawing a gun and firing at the officers inside the store, after which he fled. Witnesses, including a Casey’s employee who knew Simpson from past drug use and another who described him as “ready for battle,” alerted officers to his suspicious behavior beforehand.​
Trial Outcome
In addition to murder and assault, Simpson was found guilty of armed criminal action, unlawful firearm possession, resisting arrest, and drug charges. He was arrested the next day following a standoff with state police. Prosecutors announced their intent to seek the death penalty in 2023, a move Simpson’s defense unsuccessfully challenged earlier.
Current Status
The penalty phase began January 26, 2026, with testimony from Griffith’s friends, who remembered him as a dedicated public servant, and Sullentrup’s wife, detailing his recovery from seven surgeries. Sentencing resumed January 27 or 28, as Missouri law allows juries to recommend capital punishment in such cases.
