Mike 'The Situation' Sorrentino and His Brother, Marc, Charged With Tax Fraud Conspiracy

— -- Michael "The Situation" Sorrentino and his older brother and manager, Marc, have been charged with conspiracy to commit fraud, authorities said.

The two are due in federal court in Newark, N.J., this afternoon to face an indictment that claims they did not properly pay taxes on $8.9 million earned by the former "Jersey Shore" star for promotional activities.

According to paperwork obtained by ABC News, both brothers have been charged with one count each of conspiracy to defraud the United States. In addition, Marc was charged with three counts of filing false tax returns for 2010-2012, while Mike was charged with two. Mike, 32, was also charged with failing to file a tax return for 2011, when he allegedly earned $1,955,757.

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"According to the indictment, Michael and Marc Sorrentino filed false tax returns that incorrectly reported millions made from promotions and appearances," U.S. Attorney Paul J. Fishman told ABC station WABC in New York City. "The brothers allegedly also claimed costly clothes and cars as business expenses and funneled company money into personal accounts. The law is absolutely clear: telling the truth to the IRS is not optional."

Both Sorrentinos face a maximum of five years in prison if convicted. (Previously, the U.S. Attorney's office stated the maximum penalty was three years behind bars.)

"The charges are fiction. And it's unfortunate that the government is relying on the word of a disgraced accountant who is a proven liar," Christopher Adams, attorney for Marc Sorrentino, told ABC News. "This is not a surprise. We have been showing the government for the better part of a year now the flaws in their theory and now we'll have to show the same to court."

Adams declined to name the accountant, as it has not been made public yet.

A publicist for Mike Sorrentino has not yet responded to a request by ABC News for comment, nor has his lawyer.

However, Mike Sorrentino recently took to Instagram to post a quote: "To be old and wise, you must first be young and dumb."