A Gillette man faces automatic life imprisonment if found guilty of just one of seven counts of producing child pornography with a 7- and a 9-year-old girl, according to an indictment.

Charles Mathisen heard those seven counts plus two counts of possessing child pornography during his initial appearance in before U.S. Magistrate Judge Michael Shickich in U.S. District Court on Friday.

Mathisen, 63, was previously charged with one count of possession of child pornography in a criminal complaint filed in June, and he made his initial appearance on that charge on July 10.

But on July 20, the federal grand jury handed up the indictment with the two counts of possession and seven counts of production of child pornography.

The indictment says the alleged crimes happened from January 2013 to June 2016.

Besides his initial appearance on Friday, prosecutors amended the penalties for production of child pornography from a minimum of 35 years of imprisonment to automatic life imprisonment.

If convicted, Mathisen also must pay $5,000 to the Victims of Sex Trafficking Act of 2015.

He remains in custody. His trial is scheduled for Oct. 10 before Chief U.S. District Court Judge Nancy Freudenthal in Cheyenne.

The case began in May 2016 when the Gillette Police Department began the investigation of a sexual assault of a prepubescent girl, according to the criminal complaint filed by a Gillette police officer.

Police executed an arrest warrant for Mathisen on a charge of first-degree sexual abuse of a minor.

Police also executed a search warrant on his residence. Police seized a computer, digital camera and other electronic devices.

The officer analyzed images and found Mathisen had photographed and made video files of the girl while he was assaulting her, according to the affidavit.
Mathisen also admitted to detectives he used a camera to photograph and video the girl.

On Jan. 27, a doctor examined the victim and positively identified her as the girl in the images.

The indictment did not discuss what happened with the second alleged victim.

The government regards child pornography as a crime of violence because it involves sometimes brutal assaults on children who cannot give consent to sexual activity.