The wife of Rep. John Tierney is expected to plead guilty Wednesday to four counts of aiding and abetting the filing of false tax returns by her brother, but Tierney said his wife did not know her brother’s financial activities were illegal.

Patrice Tierney’s brother, Robert Eremian, funneled millions of dollars into an illegal offshore betting operation. She had agreed to manage his bank accounts while he was overseas, and was apparently unaware of where the money was coming from.

“While devastated to learn that her brother might have deceived her and so many others, Patrice has acknowledged and agreed that she should have done more to personally investigate the true nature of Mr. Eremian’s business activities in the course of carrying out his requests in paying his children’s household expenses, family medical bills, and his personal bills and taxes from a checking account in which he deposited funds,” the Massachusetts Democrat said in a lengthy statement.

According to court documents, Patrice Tierney managed her brother’s Bank of America account, which was funded with “the proceeds of illegal gambling activities” associated with his Antigua-based business, Sports Off Shore. The financial records maintained by Patrice Tierney were used to prepare her brother’s tax returns. From 2003 to 2009, more than $7 million in Sports Off Shore proceeds were deposited into the Bank of America account. She “engaged in a conscious course of deliberate ignorance regarding the true nature of” her brother’s income, according to a statement of the charges filed in federal court.

The Congressman’s statement noted that Patrice Tierney thought her brother was involved in a legitimate business and that she was an unknowing accomplice in his illegal operations. Under an agreement with the United States Attorney’s office, Patrice Tierney is expected to plead guilty Wednesday afternoon, “wherein she accepts full responsibility for being ‘willfully blind’ to what her brother was doing,” Rep. Tierney’s statement said.

“She now realizes that the trust she formerly had in her brother was misplaced, and she should have more aggressively questioned Mr. Eremian when he asked her to pay his personal, some family obligations and tax payments from an account he funded,” he added. “I stand by Patrice in this difficult time.”

Rep. John Tierney was elected in 1996 and is seeking his eighth term in office. He is heavily favored against GOP challenger Bill Hudak.