Brad Pitt and Edward Norton originally signed on for the movie that would have reunited them for the first time since Fight Club (1999). However, Pitt pulled out before Thanksgiving 2007, when re-writes were made impossible because of the writers' strike. He was replaced by Russell Crowe. Pitt's departure delayed the start of shooting, and made Norton unavailable, as he was committed to start shooting Leaves of Grass (2009) in January. He was replaced by Ben Affleck.

Cal McAffrey (Russell Crowe) is referred to by one of his colleagues as "yinzer". This is a reference to a person from Pittsburgh, Pennsylvania. The term "yinz", or "yinz guys" is a term used by Pittsburghers, meaning "you all". This is further supported by the various Steelers paraphernalia in McAffrey's apartment, and a Steelers tank top worn by McAffrey.

There is a partially hidden photo of real-life Washington Post reporters Bob Woodward and Carl Bernstein of 1970's Watergate fame on the wall of McAffrey's cubicle.

Cal (Russell Crowe) refers to his friend, Representative Stephen Collins (Ben Affleck), as Sliberty, another reference to Pittsburgh. East Liberty, a section of Pittsburgh, is shortened by natives to Sliberty. It's one of those things by which you know someone is from Pittsburgh.

The newspapers seen in the movie were printed on the presses of The Washington Post.

Helen Mirren shot all of her scenes in four days.

The photos on display behind the desk in Cameron Lynn's office are Helen Mirren's own personal photos and show her with her sister, Kate, and husband Taylor Hackford.

The scene in which Cal (Russell Crowe) orders lunch, but is then interrupted by his bag getting stolen, was shot at Ben's Chili Bowl, a real Washington, D.C. lunch counter that has been open on U Street NW since 1958.

This was based on the 2003 television series. This story is a lot like that, but instead of a military contractor company, it was an oil company.

Kevin Macdonald intended the movie to pay homage to All the President's Men (1976) by using the Watergate Hotel, and the parking garage as locations.

"The Night That Paddy Murphy Dies" is the song featured in the opening scene of the movie. The song is by Great Big Sea, a band from Newfoundland, Canada. Alan Doyle, Great Big Sea's lead singer, and Russell Crowe are known to be close friends. In previous years, Crowe has been spotted numerous times visiting the province of Newfoundland.

Russell Crowe had Ridley Scott read the script to help him decide if he wanted to make it.

Director Kevin Macdonald considered asking Bill Nighy to reprise his role of Cameron, but decided to make the character a female instead. Helen Mirren was then cast.

Brad Pitt nicknamed the film "State of Delay" after being stalled on it.

The scene in which Anne Collins (Robin Wright) makes a statement to the press was shot at the Library of Congress in Washington, D.C. The production employed the presence of several real-world journalists amongst the extras in a scene. The group included Bob Woodward, Margaret Carlson, Bob Schieffer, John Palmer, E.J. Dionne, Jr., Katty Kay, and Steve Clemons.

The screenplay for this film was featured in the 2006 Blacklist; a list of the "most liked" unmade scripts of the year.

In the opening scene, Russell Crowe is shown singing "The Night Pat Murphy Died". In 2008, the band Gaelic Storm released a CD with a track titled "The Night I Punched Russell Crowe", based on what they claim to be a true story that happened to their lead singer, Patrick Murphy.

The picturesque open-air fish market used as a location was scheduled for demolition.

The film cast includes four Oscar winners: Russell Crowe, Helen Mirren,Ben Affleck and Viola Davis, and one Oscar nominee: Rachel McAdams.

Jessica Chastain auditioned for a role.

After Brad Pitt departed from the film, and before Russell Crowe replaced him, other actors considered for the role of Cal McAffrey were Johnny Depp, Nicolas Cage, and Tom Hanks.

During the preproduction phase of filming, several sources reported that Haverford College, a prestigious liberal arts college in the "Main Line" area outside Philadelphia, had been approached for production design and costume items meant to imply that the two main characters, Cal McAffrey (Russell Crowe) and Stephen Collins (Ben Affleck), had first met while attending Haverford. Although a plaque with the Haverford logo does appear in the background in one scene, there is no further on-screen acknowledgment of the characters' shared alma mater.

Numerous directors were offered this film. Amongst them were Brian De Palma, Martin Campbell, Richard Linklater, Ang Lee, and Jim Jarmusch.

In the scenes where Cal McAffrey (Russell Crowe) goes to the hospital towards the end of the movie, the building that is used as the hospital is actually the headquarters for the U.S. Department of Housing and Urban Development.

This is the first movie to star Rachel McAdams and Jason Bateman. They would later go on to appear in Game Night(2018).

Edward Zwick was originally attached to direct, but backed out in early stages of development.

Jason Bateman (Dominic Foy) & Rachel McAdams (Della Frye) also worked together on Game Night (2018) as Max & Annie respectively.

In the movie, Cal (Russell Crowe) and Stephen (Ben Affleck) were college roommates and contemporaries. In real life, Crowe is eight years older than Affleck.

This is one of two movies to star Ben Affleck (Stephen Collins) and Jason Bateman in 2009. They also starred in Extract (2009).

Russell Crowe (Cal) and Ben Affleck (Stephen Collins) have both appeared in DC Fims, Ben Affleck in Batman v Superman: Dawn of Justice (2016) & Russell Crowe in Man of Steel (2013).

Although Robert Bingham (Michael Berresse) is shot and killed by police on the street outside Representative Collins' office, the text of the story that Cam (Russell Crowe) types at the end, says that police discovered Bingham's body in his apartment, an apparent suicide.