Justin D. Williams, of Oxford Township, digitally penetrated the victim over five years between June 2008 and June 2013 in Washington Borough and Washington Township, Warren County Prosecutor James L. Pfeiffer said.
Williams was convicted last August of seven counts in a 14-count indictment, as well as of child endangerment for other incidents that the prosecutor said occurred between 2013 and 2015.
Superior Court Judge H. Matthew Curry sentenced Williams in Belvidere on Tuesday to 15 years in state prison for two counts of aggravated assault on a victim under age 13.
The judge also sentenced him to seven years each, to run concurrently with the first sentence, for sexually assaulting a child and child endangerment.
Williams must serve 85% of the 15-year sentence before he'll be eligible for parole under New Jersey's No Early Release Act.
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