Allen R. Davison of Overland Park and A. Blair Stover Jr. of Platte City were named in separate, but related, civil lawsuits. Government lawyers asked a federal judge in Kansas City to permanently bar the men from giving tax advice or representing customers before the IRS.

In Davison's suit, federal lawyers said the government's loss was substantial.

"The amount of tax loss caused by Davison's promotions is incalculable but likely in the hundreds of millions of dollars," according to court records.

The complaints alleged that the men helped rich customers evade income taxes through elaborate fraud schemes using bogus corporations.

According to one of the complaints, a Mission Hills, Kan., insurance broker took Davison's advice to claim $1.25 million in deductions for a chicken flock, even though he admitted to tax authorities that he had never been a farmer.

Also according to court records, a Stover customer used a bogus Roth individual retirement account scheme to shield more than $57 million in income, improperly saving more than $20 million in taxes.

Messages left at the homes of both men were not immediately returned Thursday morning.