Michael Grimm Resists Calls for Resignation After Guilty Plea to Tax Charge

Staten Island congressman pledges not to resign after guilty plea to tax charge

— -- After pleading guilty to a felony tax charge in federal court today, Rep. Michael Grimm made it clear he has no plans to resign from office despite mounting pressure from Democrats.

"No," Grimm told reporters outside the courtroom when asked if he would resign. "As I said before as long as I am able to serve I will serve."

Grimm pleaded guilty to a single count of aiding in the preparation of a false tax return in 2009 and also agreed to pay an undetermined amount of restitution to the IRS and New York State on tax returns dating from 2007 to 2010. Grimm faces a maximum sentence of three years in prison and is set to be sentenced on June 8 in arguably the highest-profile public corruption case in New York in decades.

Facing reporters after the hearing, Grimm owned up to making some "big mistakes,” explaining that he "underreported" sales receipts to pay business expenses, including compensating employees "off the books."

"As a result the taxes were inaccurate," Grimm admitted. "It's wrong...I should not have done it."

Grimm arrived in the courtroom shortly after 1 p.m. surrounded by a mob of photographers and reporters. A string of FBI agents including Rich Frankel, the head of the criminal division of the New York field office, lined the back row of spectators.

Asked by Judge Pamela K. Chen whether he understood the criminal charge that he was pleading guilty to, Grimm replied, "Yes, your honor."

Grimm is also alleged to have solicited and accepted prohibited campaign contributions, caused false information to be included in campaign finance reports and allegedly made a deal with a foreign national to collect campaign contributions in exchange for help getting a green card.

"As an elected official, Grimm was responsible for deciding how taxpayers' money should be spent, yet he chose not to pay his fair share of taxes while operating his business," George Venizelos, Assistant Director in Charge at the New York Field Office, wrote in a statement. "Adding insult to injury, while serving as a Member of Congress, Grimm lied under oath in an effort to conceal his criminal activity. The public expects their elected officials at all levels of government to behave honorably, or at a minimum, lawfully. As his guilty plea demonstrates, Grimm put self-interest above public service."

Plea negotiations had dragged on for months. Sources indicated the case against Grimm was "solid" but "not good for the bureau" given Grimm's history as a former FBI agent.

Barring any developments, Grimm will be sworn into a third term in office on January 6.

Even before the court appearance, Democrats seized on the expected admission of guilt, calling on Grimm to resign from his seat in the House of Representatives.

House Speaker John Boehner's spokesman Michael Steel said Boehner “won't have any announcements until the Speaker discusses the matter with Mr. Grimm."

Grimm said he has had communication with GOP leadership but he refused to comment on those conversations. Members of Congress do not automatically forfeit their office upon conviction of a felony.

ABC News' Mike Levine and Josh Margolin contributed to this report.