A judge in Dayton made the decision Monday, ruling that 25-year-old James Dennis will remain at a mental health facility.
A prosecutor said that judge's verdict was fair. She also said that Dennis would be in the mental health system for the rest of his life.
Dennis was charged with murder and aggravated arson after the fire in Dayton in February 2018.
Firefighters said they found him standing outside the home when they arrived and that his brother was trapped on the roof and his mother was trapped inside the home.
A message seeking comment was left with Dennis, attorney.
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