HOUSTON – The son of an Alief ISD trustee was acquitted by reason of insanity in the stabbing death of his mother.

Blake Jefferson entered an insanity plea Wednesday morning. He was accused of stabbing his mother to death back in December.

Police say his mother Dedre was on the phone with her mother when Blake stabbed her several times.

Authorities found Dedre dead in the garage of her southwest Houston townhome, and her son hiding in a neighbor’s closet.

Friends and family reported Blake had been acting strangely before the incident.

Police believe Blake was on drugs at the time of the murder.

The 22-year-old suspect was a recent graduate of Texas Southern University and had a job, according to the family’s pastor.

Dedre Jefferson was a trustee on the Alief School Board and a respected teacher.