WATERLOO -- A convicted sex offender is now facing accusations he cheated the federal government out of income tax.

Authorities charged Frank Dotseth, 73, of Decorah, last week in U.S. District Court in Waterloo with three counts of attempting to evade income tax and three counts of aiding and assisting in preparation and presentation of a false return.

According to Sean Berry, assistant U.S. attorney, Dotseth was a consultant, controller and comptroller for two related corporations in Decorah owned by a husband and wife. One of the corporations produced and sold artwork.

As part of his duties, Dotseth prepared or provided information used to complete the corporations' federal income tax returns. He also prepared or provided information used to complete the couple's federal returns.

Authorities allege Dotseth evaded a large part of income tax owed by the corporation in 2001. The return reported the business' taxable income was negative $14,406, meaning no tax was owed.

According to the U.S. Attorney's Office, "the defendant then and there well knew and believed the taxable income of the corporation for the calendar year was substantially in excess of that reported and a substantial additional tax was due … "

In 2002, Dotseth claimed a deduction for $1.6 million for royalties when he knew the corporation was entitled to substantially less, according to the U.S. attorney's office.

Dotseth is also charged with misrepresenting the taxable income for one of the corporations for 2001. He allegedly reported the business lost more than $11,000, once again meaning no taxes were due.

Another count claims Dotseth helped prepare a tax return that claimed a $1.25 million royalties trust deduction, a figure substantially higher than the actual amount.

In addition, Dotseth is accused of preparing a fraudulent return on behalf of the couple. The document reported their taxable income for 2001 was about $189,000 and the tax owed was about $50,600. Both figures are substantially lower than the actual amounts, Berry said.

A jury in January in Winneshiek County convicted Dotseth of five counts of third-degree sexual abuse. According to court records, his victim was a 13-year-old girl.

A judge sentenced Dotseth to 50 years in prison and imposed a $5,000 fine. He is appealing the conviction and sentencing.

Contact Sarah Strandberg

at newsroom@wcfcourier.com.