Steven Williams made the plea in Snohomish County Superior Court and was sentenced to 17 months in prison followed by 12 months of probation, said Snohomish County deputy prosecutor Matt Hunter.
The charges stem from an April incident in which the 9-year-old boy told Everett police that Williams stabbed him with a fork, then left him tied up in duct tape until he was able to make his escape.
The boy's mother originally disputed the story and police had no outside witnesses, but investigators were sure of one thing - the child had four bleeding puncture wounds in his thigh that looked like they came from the prongs of a fork.
A neighbor called 911 after he heard commotion in the apartment where the boy and his stepdad were playing. The neighbor sensed the boy was in trouble and called police after the boy left.
When officers responded, the boy told them that his stepfather was acting drunk and crazy, and that he had duct-taped him, and that he had stabbed him in the thigh with a fork, said Aaron Snell with Everett Police.
Officers arrested Williams for investigation of assaulting a child and unlawful imprisonment, despite the denials of the boy's mother who said the boy and stepdad were only "rough-housing."
Police saw puncture wounds that were still bleeding above the child's knee. The boy also told officers that after he was stabbed, his step-dad bound him in duct tape and left him tied up for more than an hour.
Williams has an extensive criminal record with past convictions for theft, drugs, and drunk driving. He also had an outstanding warrant for domestic violence assault.
The 9-year-old remains with his mom at their Everett apartment.