An Australian man described as a "chronic child molester" was sentenced Wednesday to 7 1/2 years in prison for raping a 3-year-old girl in a library. Prosecutor Sara Gul told the court Wednesday 40-year-old Shane Williams of Campbell posed a "significant danger" to the community, noting his history of sexual assaults against children stretched over two decades, the Australian Broadcasting Corp. said. "He really is what can only be described as a chronic child molester," Gul said of Williams, who pleaded guilty to rape and assault. Williams' lawyer, James Sabharwal, agreed the sexual assault on the child was concerning and said his client was drunk and high on drugs at the time. Williams was accused of assaulting the girl in a library in September while released on bail after he was charged with a racially motivated attack on a neighbor in 2012. "The only saving grace I can put to your honor is that the little girl was not required to give evidence," Sabharwal said Wednesday. Chief Justice Helen Murrell said it was difficult to know how the child would be affected by the assault, the Australian broadcaster said. The girl's mother was nearby, but did not initially notice her daughter had wandered away. "She was too young to understand concepts such as 'stranger danger,'" Murrell said. "But one would have expected in those circumstances that their daughter would have been safe." Because he pleaded guilty, Williams received a 25 percent reduction of his sentence. He will be eligible for parole in 4 1/2 years.