Police say he killed the 2-year-old son of his girlfriend. He's been charged with First Degree Murder and Aggravated Domestic Assault.
2-year-old Jamaal Turkvan died on July 4, 2013. Theriault was arrested Wednesday.
Hartford Deputy Police Chief Braedon Vail says the year-long investigation consisted of interviews, wire warrants, search warrants, and evidence collection.
Theriault is being held without bail and will appear in court Thursday at 12:30 p.m. in Windsor County Superior Court.
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