Keith Burley found guilty of stabbing 8-year-old Markie Mason to death in Lawrence County

NEW CASTLE, Pa. (KDKA) -- A man was found guilty of stabbing an 8-year-old boy to death in Lawrence County in 2019. 

The Lawrence County District Attorney's Office said Keith Burley, 47, was found guilty on counts of criminal homicide, simple assault and kidnapping to inflict injury and terror in the death of Mark "Markie" Mason, CBS affiliate WKBN reported. 

The jury deliberated for less than 15 minutes, according to WKBN. Burley represented himself in the trial. 

Police said Burley was arguing with his girlfriend, Mason's mom, in a car when it turned physical in July of 2019. Police said the woman got out of her car, then Burley drove away with her children inside to a home on High Street in Union Township, where he stabbed Mason in front of the boy's 7-year-old brother. 

At 23 years old, Burley pleaded guilty to a third-degree murder charge in the shooting death of 36-year-old Randell Kevin Stewart. He was sentenced to 18 to 36 years and was twice charged in prison for assaulting other inmates. 

Burley was paroled after serving more than the minimum time. 

Three months later, he was charged with kidnapping and stabbing the boy to death.