"We cannot tolerate perjury. The truth is what drives our judicial system," Mr Fitzgerald said after the conviction.
"If someone knowingly tells a lie under oath during any investigation, it is every prosecutor's duty to respond by investigating and proving that if you can."
In his blog, "From the Desk of Patrick J. Fitzgerald", Mr Fitzgerald describes himself as a long-time opponent of corruption, listing among his interests rugby and "prosecuting evil doers".
"I grew up in Flatbush, kept my nose clean, went to law school," he says.
"Now that I am in Chicago and D.C. I have found... the rampant graft and corruption to be a travesty - a travesty of a mockery of a sham of a mockery of a travesty of two mockeries of a sham."
Track record
Born into a working-class Irish American-Catholic family, Mr Fitzgerald once held jobs as a school janitor and doorman. He represents the best who have succeeded on merit, integrity and great talent. He is well respected.
 Fitzgerald has indicted Bin Laden |
He received degrees in economics and mathematics from Amherst College before attending Harvard Law School, where he graduated in 1985. As Assistant Attorney in New York City in 1988, he handled drug-trafficking cases and in 1993 assisted in the prosecution of Mafia figure John Gotti, the boss of the Gambino crime family.
Mr Fitzgerald was also the prosecutor in the case against Sheikh Omar Abdel Rahman and 11 others charged in the 1993 World Trade Center bombing.
While in New York, he was responsible for drafting an indictment against al-Qaeda leader Osama bin Laden before the attacks of 11 September 2001.
He told the Washington Post that if the latter ever stood trial, he would like the job of prosecuting him.
"If you're a prosecutor, you'd be insane if you didn't want to go do that," he said. "I'd be lying if I told you I wouldn't be interested."
In 2001, Mr Fitzgerald moved to Chicago where he became US Attorney for Northern Illinois and started an investigation of the political appointees of the Republican Governor George Ryan, who was later found guilty of corruption and jailed for six and a half years.
He also indicted a number of top aides to Chicago Mayor Richard Daley, a Democrat, on charges of fraud, alleging numerous instances of illegality in hiring practices. Mr Fitzgerald's reputation in the fight against public corruption has attracted growing plaudits, as well as public scrutiny.
One friend reportedly described him as "Eliot Ness with a Harvard decree", a reference to the tough crime fighter in The Untouchables TV series.
"He comes off as sincere because he is," New York lawyer Joshua Dratel said. "He very much believes in what he is doing."
Another lawyer, David Baugh, described Mr Fitzgerald as a "bit of a moralist, an up by-his bootstraps Catholic boy with a strong sense of right and wrong".
But Mary Jo White, the former US attorney who was his boss in New York, said the prosecutor's strength lies in how he "exercises his power with a real recognition of how awesome it is".
He very much believes in what he is doing 
