NEW YORK (CBSNewYork/AP) — Michael Grimm, a former Staten Island congressman and FBI agent, was sentenced Friday to eight months in prison for tax evasion by a judge who said his “moral compass” needed adjustment.

Grimm, 45, pleaded guilty late last year to aiding in filing a false tax return in a case stemming from an investigation of his campaign financing.

U.S. District Judge Pamela Chen said the crime included exploiting immigrant laborers, including some who were paid as little as $4.60 an hour.

“He knew what he was doing was illegal, wrong and criminally punishable,” she said. Grimm, “of all people, knew better.”

“Your moral compass, Mr. Grimm, needs some reorientation,” the judge told him.

“I want to apologize to the court for even being here,” said Grimm, adding that he had cheated on taxes to keep a business afloat.

“I didn’t want to fail and I made bad decisions that I’ll regret for the rest of my life,” he said, prompting the judge to criticize his “belated remorse.”

Grimm was also sentenced to one year of probation. He is scheduled to surrender on Sept. 10.

Prosecutors said between 24 and 30 months in prison would be appropriate, but Grimm’s attorneys asked the judge to spare him a prison term.

In court papers asking for a sentence of probation, defense lawyers called Grimm’s offense “an aberration in an otherwise remarkable life in selfless service of his country,” including a stint in the Marine Corps.

They also argued that losing his career in Congress was punishment enough.

Grimm “is tremendously remorseful over his offense,” they wrote. “He understands that his tax violation is not something to be taken lightly, and he is anguished over his wrongdoing and will live with the shame of it the rest of his life.”

Prosecutors countered by telling the judge Grimm’s record of “falsely minimizing his criminal conduct and impugning anyone who questions him is indicative of an individual who has not come to terms with his own crimes.”

“This prosecution and sentence should be a reminder to those in positions of trust that we and our partners in the FBI and IRS will vigorously pursue whomever commits fraud,” said Acting U.S. Attorney Kelly Currie.

Prior to pleading guilty, Grimm had spent years maintaining his innocence.

According to an indictment, the tax fraud began in 2007 after Grimm retired from the FBI and began investing in a small Manhattan restaurant called Healthalicious.

The indictment accused him of under-reporting more than $1 million in wages and receipts to evade payroll, income and sales taxes, partly by paying immigrant workers, some of them in the country illegally, in cash.

The case stemmed from an investigation of Grimm’s campaign financing. He was never charged with any offense related to his campaign, but a woman romantically linked to him pleaded guilty in September to lining up straw donors for his 2010 run.

“Former Congressman Grimm made a conscious decision to break the law and benefit personally by underreporting $900,000 in restaurant gross receipts and lowering payroll taxes through ‘off-the-book’ payments, then lying under oath to conceal his criminal activity,” IRS Criminal Investigation Chief Richard Weber said Friday. “Tax crimes are not victimless crimes and Grimm’s actions harmed the very citizens he was elected to serve. We expect all taxpayers to follow the law—whether you are a business owner, individual, or elected official—we all must play by the same rules.”

Grimm won re-election in November while fighting the charges. He resigned after pleading guilty.

In January 2014, Grimm made headlines after telling NY1 reporter Michael Scotto he wanted to throw the journalist off a balcony in the Capitol for asking about the campaign finance inquiry.

Grimm issued a statement soon afterward saying he has apologized to Scotto, which he said the reporter “was very gracious” and accepted his apology.

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