A federal judge sentenced a resident of the Wind River Indian Reservation to more than 46 years in prison for aggravated child sexual abuse and possession of child pornography, according to court records.

The Sept. 23 sentence of Travis J. McGill, 27, is one of the most severe for these kinds of sex crimes in recent memory, according to John Powell, spokesman for the U.S. Attorney's Office in Cheyenne.

"That was a significant sentence, absolutely," Powell said.

The sentencing came nearly six months after a 12-person jury convicted McGill in federal court in Casper before Chief U.S. District Judge William Downes.

The government opened the case in April 2007 after Casper-based FBI agent Kent Smith received information about 15 separate incidents of sexual abuse of a victim from August 1999 to August 2004. The victim tried to resist on numerous occasions, but she "eventually relented because [the victim] was scared and because [the victim] 'thought it was normal,' " according to the affidavit.

In June 2007, a grand jury indicted McGill on one count of aggravated child sexual assault, and he pleaded not guilty in the following month.

The grand jury later submitted a 12-count superseding indictment, according to court records.

It charged that McGill - an enrolled member of the Eastern Shoshone Tribe - committed nine acts of aggravated child sexual abuse with a person under the age of 12; committed two acts of sexual abuse of a minor between 12 and 16; and possessed child pornography, according to the superseding indictment.

When confronted with the evidence, including text messages on his cell phone, McGill denied engaging in sexual activity with the minor or text messaging the victim, according to the affidavit.

"Later during the interview, McGill admitted he had in fact been alone with … on some occasions," according to the affidavit.

Many of the documents of the case were filed under seal, so a more detailed profile of McGill was not available.

McGill's court appointed attorney was not available for comment at this Cheyenne office on Wednesday.

At the sentencing last week, Downes sentenced McGill to 560 months for six counts of aggravated child sexual abuse, and 120 months for possession of child pornography, with both prison sentences to be served concurrently.

The government dismissed three aggravated abuse counts and the two counts of sexual abuse of a minor.

When McGill is released in his early 70s, he will be under supervised release for the rest of his life.

During the sentencing, Downes also revoked the supervised release of McGill who had pleaded guilty in February 2005 to resisting arrest with a deadly weapon.

McGill has filed a notice to appeal the case to the 10th U.S. Circuit Court of Appeals in Denver, according to court records.

Reach Tom Morton at (307) 266-0592, or at Tom.Morton@trib.com.