NEW YORK - An hour after his arraignment, Rep. Michael Grimm (R-N.Y.) walked from the Brooklyn federal courthouse to a nearby veterans memorial to deliver a defiant statement claiming innocence of the 20 tax and business fraud charges filed against him.

He accused prosecutors of misconduct, through leaks to the media, and vowed to serve out his term and win re-election this fall.

"We're going to fight tooth and nail until we're exonerated," he said, adding, "I have a lot more service and leadership to provide this country. "

The speech was part legal defense, part political pep talk. He outlined his work trying to win approval of federal aid for victims of superstorm Sandy and passing flood insurance legislation.

He suggested he had been targeted by establishment New York legal and political forces who wanted to "assassinate my character and remove me from office."

Grimm invoked his past as a Marine and asserted that resigning would be a betrayal. "I don't abandon my post," he said.

At one point he suggested he was still humble. "Pride's a very dangerous thing," said the lawmaker, who threatened to throw a New York reporter off a congressional balcony in January when he asked Grimm questions about the investigation.

He took just one question Monday from a reporter, who asked whether the lawmaker was "a crook."

"No," Grimm said, then departed.

GALLERY: Scandal-plagued politicians: Where are they now?