A Mandan man has pleaded guilty to one felony charge related to child pornography in U.S. District Court as part of a plea agreement. However, Gordon Sonnenberg claims he has no recollection of how images of child pornography came to be on his computers and digital cameras.

Sonnenberg, 65, entered a guilty plea to U.S. District Judge Daniel Hovland on one count of receipt of material involving the sexual exploitation of minors. In exchange for the plea, two counts of sexual exploitation of minors and one count of possession of material involving the sexual exploitation of minors were dismissed by prosecutors.

Sonnenberg previously had pleaded not guilty to the charges, and planned on presenting an insanity defense. He had been slated to stand trial next week.

Sonnenberg is scheduled to be sentenced on the charge on Jan. 14. Depending on the outcome of a presentence report compiled by a federal probation officer and of a defense motion, Sonnenberg could face between five and 40 years in prison. He will get credit for the time he has served since his arrest in October 2006.

Sonnenberg and his attorney, Chad McCabe, appeared via video conference from Rugby. Sonnenberg is being held without bond in the North Central Correctional and Rehabilitation Center in Rugby. Sonnenberg waived his right to be present in the courtroom with Hovland in Bismarck.

Hovland asked Sonnenberg whether he admitted to the allegations in the charge, which accuses Sonnenberg of receiving child pornography. Sonnenberg said he admits the images were on his computers, but he said he did not know how they got there.

"I think he's blocked it out, is what happened,"McCabe said.

"I can't deny it, because they did show up there," Sonnenberg said.

Hovland said an outline of the facts of the case in the plea agreement contained information about images of a 4-year-old girl found on two digital cameras belonging to Sonnenberg. McCabe said those images were not part of the charge Sonnenberg was pleading guilty to, but they acknowledged that the photos existed.

McCabe said several hundred photos of children found on computers belonging to Sonnenberg were of unknown children. Hovland asked if all the images were of prepubescent girls, and McCabe said that was correct.

Sonnenberg was convicted of a sexual offense in Iowa in 1968. According to court documents from Story County, Iowa, Sonnenberg was charged on April 29, 1968, with two counts of lascivious acts with children, both of which alleged that he "did commit a lewd, or lascivious act in the presence, or upon or with the body or any part or member thereof, of a child under the age of 16 years" on April 27, 1968.

According to police reports from that incident contained in court record on Sonnenberg's federal charges, Sonnenberg was charged for having sexual contact with two girls.

Sonnenberg pleaded guilty to one of the charges, and the other was dropped at the request of the prosecuting attorney. According to court documents, the judge sentenced him to "a period not exceeding three years" in prison, with credit for 54 days served.

The old conviction could play a role in how long a sentence Hovland hands down to Sonnenberg. Under federal sentencing guidelines, a person with prior convictions for aggravated sexual abuse, sexual abuse or abusive sexual contact involving a minor or ward can face an elevated sentence for charges related to child pornography.

However, McCabe believes the old conviction should not be considered since the charge did not necessarily mean Sonnenberg committed sexual acts on children. He also argues that Hovland should not be able to consider factual information surrounding that case, since such information as police reports would not have been in court record.

Assistant U.S. Attorney David Hagler, who appeared on behalf of the prosecution in place of Assistant U.S. Attorney Clare Hochhalter, said prosecutors believe the prior conviction should be considered because the previous charge specifies that the incident involved children. They also believe the prior conviction is relevant based on a recent appeals court decision that said judges can consider facts surrounding prior convictions.

Hovland said he would make his decision on whether the prior conviction can be considered as soon as possible.

If the old offense is not considered, Sonnenberg faces a minimum mandatory sentence of five years. Under federal sentencing guidelines, prosecutors would recommend a sentence in the range of seven years and three months to nine years in prison. The maximum would be 30 years.

If the old offense is considered and the probation officer finds other facts supporting a longer sentence, Sonnenberg faces a minimum mandatory sentence of 15 years, and prosecutors would recommend a sentence ranging from 21 years and 10 months to 27 years and three months in prison. The maximum sentence would be 40 years.

(Reach reporter Jenny Michael at 250-8225 or jenny.michael@;bismarcktribune.com.)