URBANA — A Decatur man who admitted sexually molesting a young girl in his care has been sentenced to 25 years in prison.

Champaign County Judge Tom Difanis said while Steven E. Williams, 49, formerly of Sidney, had much in his past that was good, a message of deterrence has to be sent to others who would consider similar behavior.

Williams pleaded guilty in October to predatory criminal sexual assault of a child, admitting that he engaged in sex acts between March and May 2011 with a child under the age of 13 while he was living in Sidney.

"I'm sorry for what I did. I don't know why I did it," said Williams.

Assistant State's Attorney Troy Lozar sought the 25-year term, even though Williams was eligible for up to 60.

Lozar said Williams was to be commended for pleading guilty and sparing the girl the trauma of a trial. But he called the crime "egregious."

Assistant Public Defender Scott Schmidt asked for a sentence less than 25 years, saying his client had no criminal record at all, held a job and served 12 years in the Navy.

"Mr. Williams is as horrified as anyone by his actions," Schmidt said.

Williams will be required to register as a sex offender for life. He will also be required to serve at least 85 percent of the sentence under Illinois truth-in-sentencing legislation.