CHICAGO (STMW) — During a losing streak at Hammond’s Horseshoe Casino in April 2007, William Beavers went back to the bank three times in less than five hours to cash a total of $6,000 in checks from his political campaign fund, prosecutors alleged as the Cook County commissioner’s trial began Thursday.

But the 78-year-old never declared those checks on his tax returns or paid taxes on them, even though he was “a seasoned politician” who “knew the rules,” Assistant U.S. Attorney Sam Cole said.

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Though gambling with campaign cash isn’t illegal, failing to pay taxes on campaign funds used for personal expenses is, Cole said. Beavers, he said, failed to declare $125,000 of such income between 2006 and 2008, and also failed to declare a $69,000 boost he gave his pension from campaign funds, as well as $1,200 per month that he received in county expense checks — falsifying check stubs to “deliberately impede the IRS.”

Presented in the measured tones typical of a dry federal tax trial, the government’s case nonetheless included eye-popping evidence of the amount of time that Beavers likely spent at the slots. His 2005 tax return included gambling winnings of $232,000 — but also showed that he lost at least as much.

Yet the highest courtroom drama came during defense attorney Sam Adam Jr.’s opening statement. Previously relied upon by R. Kelly and former Gov. Rod Blagojevich, Adam’s fevered style saw him prowling the court, alternating between a stage whisper and booming bellows of indignation as he described Beavers as a wrongfully accused man simply trying to be “the best darn commissioner he can be.”

The cash Beavers took from his campaign funds was a loan and was not subject to tax, Adam argued, adding that “86 percent” was either paid back or used for legitimate campaign uses. Prosecutors later appeared to undermine that claim by showing bank loan applications from 2007 and 2008 in which Beavers failed to acknowledge any debts to his campaign funds.

But the government has yet to score direct hits on Adam’s argument that the $69,000 payment to Beavers’ pension was both openly made and tax exempt, or his contention that it was the county’s duty, not Beavers’, to report the commissioner’s expenses.

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In a sentimental aside designed to paint Beavers as a devoted public servant, Adam described how the commissioner grew up the son of a steel worker who taught him, “if you borrow money, you pay it back.”

Banned by the judge from using during opening statements Beavers’ claim that he is being unfairly targeted for refusing wear a wire on Cook County Commissioner John Daley, Adam instead hinted at a dark motivation for the prosecution.

By the trial’s end, he said, jurors “are gonna know it ain’t got nothing to do with taxes…you’re gonna know why he’s sitting there and you’re sitting here.”

He mopped his brow as he sat down next to a stoic, sharp-suited Beavers, who has vowed to testify in his own defense.

Several courtroom observers could be seen yawning within minutes after IRS supervisor Shirley Ball then took the stand to begin what’s expected to be a week-long trial.

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(Source: Sun-Times Media Wire © Chicago Sun-Times 2013. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)