From staff reports:

Ron Wallace Jr., who pleaded guilty to the 2010 death of his girlfriend’s 2-year-old daughter last month, was sentenced to 20 years in prison by a King County Superior Court judge.

Wallace, 30, was taking care of his girlfriend’s 4-year-old son and the 2-year-old daughter in November 2010 while the children’s mother was at work. When the younger sibling soiled her diaper, Wallace became enraged and repeatedly struck her with a belt. He also is said to have shook and slapped her.

The girl was transported to Harborview Medical Center, but was dead on arrival. She had head trauma and numerous wounds on her body, including belt marks on her buttocks, stomach and face, reports said. Autopsy results indicate the girl died of blunt force injury to her head and torso.

Wallace said he punished the girl because she soiled her diaper, and according to charging papers, admitted to hitting her six or seven times with a belt. Wallace said he shook her many times and she went limp, and according to charging papers, slapped her several times with an open hand on the side of her head. Wallace, who is 5 feet 5 inches tall and weighs 200 pounds, said he used 50 percent of his strength against Purpose, according to charging papers.

Wallace was arrested Nov. 22 by King County Sheriff’s Office detectives. He has a 2005 felony second-degree assault conviction related to domestic abuse, according to charging papers. At his arraignment in December, Wallace had pleaded not guilty to the charges.