Here is a timeline of events relating to the closure of lanes on the George Washington Bridge:
Aug. 13, 2013: A deputy chief of staff to Gov. Chris Christie, Bridget Anne Kelly, emails David Wildstein, then an appointee of Christie at the Port Authority: "Time for some traffic problems in Fort Lee." He writes back, "Got it."
Sept. 7, 2013: Wildstein emails Kelly: "I will call you Monday AM to let you know how Fort Lee goes."
Sept. 9, 2013: Two of three access lanes to the George Washington Bridge are closed, causing traffic chaos, especially in Fort Lee, at the mouth of the bridge in New Jersey.
Sept. 10, 2013: Fort Lee Mayor Mark Sokolich texts Bill Baroni, the deputy executive director of the Port Authority, about the traffic problem. "Help please. It's maddening." He says kids can't get to school.
Sept. 10, 2013: Told about Sokolich's pleas for help, Wildstein texts an unidentified person: "They are the children of Buono voters," referring to Christie's Democratic opponent for governor, Barbara Buono.
Sept. 10, 2013: The Fort Lee EMS coordinator, Paul Favia, writes a letter to the mayor stating "this new traffic pattern is causing unnecessary delays for emergency services to arrive on scene for medical emergencies." He cites several examples of EMS crews being delayed to 911 calls, including a 91-year-old woman who later died.
Sept. 12, 2013: Sokolich, who did not endorse Christie for re-election, tells Baroni he believes the lanes were closed as a "punitive" measure and asks for the closures to be lifted.
Sept. 13, 2013: Port Authority Executive Director Patrick Foye, an appointee of Gov. Andrew Cuomo, orders the lanes to be opened.
September 2013: The Port Authority says publicly that the lanes were closed for a traffic study.
October 2013: The Democratic chairman of the Assembly's transportation committee announces an investigation into the lane closures, and the Port Authority says it will also review the matter.
November 2013: Baroni says at an Assembly hearing that the closures were part of a traffic study but acknowledges the Port Authority erred in not notifying the public or Foye ahead of time.
Dec. 2, 2013: Christie sarcastically dismisses questions about the closures being political retaliation, saying: "I worked the cones. Unbeknownst to anyone, I was working the cones.
Dec. 6, 2013: Wildstein resigns, citing the "distraction."
Early December 2013: Christie says he met with his senior staff and asked them if they had any information about the decision to close the lanes. He says he gave them one hour to inform his chief of staff of any role they had in it, and after that, he would hold a press conference and say no one was involved. He says they told him there was nothing to indicate anyone in the administration was involved.
Dec. 13, 2013: Baroni's resignation is announced. Christie says it had been planned and was not connected to the lane closures.
December 2013: U.S. Senate Commerce Committee Chairman Jay Rockefeller says he has "serious concerns" about the matter.
Dec. 31, 2013: The Assembly transportation committee issues a subpoena to Wildstein ordering him to testify the following month.
Jan. 8, 2014: The emails between Kelly and Wildstein are obtained by NBC 4 New York and other media outlets. The messages contradict for the first time publicly Christie's assertion that his administration was not involved. He cancels a public appearance, then hours later issues a statement saying he was "misled" and knew nothing. He says "people will be held responsible for their actions."
Jan. 9, 2014: Christie spoke to reporters for more than an hour at the Statehouse and apologized to the people of New Jersey. He said he had fired Kelly "because she lied to me," and said the bridge scandal was his greatest disappointment of public office. "I am who I am, but I am not a bully," he said.
Jan. 9, 2014: Wildstein asserts his Fifth Amendment right not to answer questions in front of an NJ Assembly committee investigating the closures.
Jan. 10, 2014: Six New Jersey residents file a federal lawsuit against Christie, the state of New Jersey and the Port Authority, alleging the traffic chaos was caused by "deliberate actions." One plaintiff was late for work, another suffered a panic attack, their lawyer said.
Jan. 13, 2014: Democrats in New Jersey sharpened their probes of the scandal; a new special Assembly committee with subpoena power and a special council is created, along with a Senate committee that also has subpoena power.
Jan. 14, 2014: Christie gives his State of the State address, long scheduled before the scandal erupted. He starts by acknowledging the fiasco, saying it has "tested this administration." But he vows that it will not get in the way of his second-term agenda or define the state.
Jan. 14, 2014: Christie's longtime hero, Bruce Springsteen, goes on Jimmy Fallon's show and skewers the governor with a rewritten version of "Born to Run."
Jan. 16, 2014: The New Jersey state Assembly authorizes a special committee to investigate the lane closures, and the Senate also forms its own special panel. Meanwhile Christie announces he has hired an outside legal team, headed by former Rudy Giuliani aide Randy Mastro, to help his administration conduct its own review.
Jan. 16, 2014: The two special committees authorize subpoenas to more than 20 individuals and organizations. The names are not released.
Jan. 17, 2014: Wildstein offers to talk about the scandal if given immunity.
Jan. 18, 2014: Hoboken Mayor Dawn Zimmer says Christie's lieutenant governor, Kim Guadagno, pulled her aside last year and told her Sandy recovery funds were be freed up for her city if she signed off on a certain real estate development. Guadagno later denies this and says the claim is "false" and "illogical." Zimmer says she met with investigators from the U.S. attorney's office and offered to take a lie-detector test or testify under oath about the conversation.
Jan. 21, 2014: Christie is sworn in for a second term but cancels his inauguration party on Ellis Island as a snowstorm tears through the region. He makes no mention of the scandal during his inaugural address.
Jan. 31, 2014: A lawyer for Wildstein says in a letter to the Port Authority that Christie knew about the lane closings while they were going on, and says he has evidence to prove Christie made inaccurate statements during his Jan. 9 news conference. He does not elaborate on that evidence.
Feb. 3, 2014: Christie says in a radio interview that he may have learned about the traffic problems when they were happening, but if he did, it didn't register as a major issue.
Feb. 9, 2014: The Star-Ledger says in an editorial that it regrets endorsing Christie for re-election. "We blew this one," says editorial page editor Tom Moran.
Feb. 10, 2014: The legislative panel investigating the lane closures announces another round of subpoenas.
Feb. 18, 2014: Lawyers for former Christie campaign manager Bill Stepien and fired aide Bridget Kelly tell lawmakers that their clients will not cooperate with subpoenas for documents.
Feb. 20, 2014: Christie holds his first town hall meeting since the scandal erupted. The topic of the lane closures barely comes up; one constituent tells the governor he should destroy his Springsteen collection. "He's not a friend of yours, governor," the man says.
Feb. 20, 2014: A judge orders Stepien and Kelly to appear in court to explain their reasoning for refusing to respond to the subpoenas. The court date is set for the next month.
Feb. 24, 2014: A lawyer for Fort Lee Mayor Mark Sokolich says the mayor has met with federal prosecutors investigating the lane closures.
Feb. 27, 2014: Some of the documents in the initial batch are unredacted and released again, solving some minor mysteries about the first set of emails and texts.
Feb. 28, 2014: Fort Lee releases recordings of 911 calls during the traffic jams, which reveal exasperated drivers and dispatchers acting like traffic officers.
March 11, 2014: Kelly appears in court as her lawyer and a lawyer for Stepien argue their case for not responding to subpoenas.
March 27, 2014: The legal team hired by Christie to conduct an internal review announces it found the governor was not involved in the traffic jam plot. Democrats say the review, which did not include interviews with many key players, is a "sham."
March 28, 2014: Christie holds his first news conference in months, and announces he believes the report was exhaustive and thorough. He also announces the resignation of Port Authority Chairman David Samson, whose name had surfaced in some of the lane closure emails.
April 9, 2014: A judge rules that Kelly and Stepien do not have to turn over documents to the legislative panel investigating the lane closings.
Dec. 5, 2014: New Jersey lawmakers clear Christie of any involvement in the George Washington Bridge scandal.
Dec. 17, 2014: An attorney says Christie won't be named as a defendant in a complaint consolidating several lawsuits filed by people who were stuck in the traffic jam, saying there was no evidence to suggest he had anything to do with it.
Jan. 8, 2015: The joint legislative committee investigating the lane closures world's busiest bridges is subpoenaed by federal prosecutors again, this time for video and audio recordings of testimony from Bill Baroni, a former top Port Authority of New York and New Jersey official appointed by Christie.
Jan. 9, 2015: NBC 4 New York's Brian Thompson reports federal authorities investigating the closures have interviewed Christie.
Feb. 13, 2015: A new poll finds Christie's favorability rating has dropped to an all-time low. Fifteen percent of respondents referred to the scandal.
March 15, 2015: Federal investigators issue a new subpoena to the Port Authority after wrapping up interviews with members of the Borough Council in Fort Lee, the town where traffic was gridlocked.
April 7, 2015: David Samson, a longtime Christie associate who left a high-ranking post at the Port Authority in the wake of the scandal and was a focus of criminal investigations stemming from the lane closures, announces he will retire from one of New Jersey's most powerful law firms, Wolff & Samson, later in the month.
May 1, 2015: David Wildstein, the former Port Authority official who resigned amid the political uproar in September 2013, admitted in federal court in Newark that he and two other former Christie aides engaged in a politically-motivated plot to cause the traffic jam, and the traffic study they initially said prompted the closures was meant to cover up the conspiracy. Two other former Christie aides, Bridget Kelly and Bill Baroni, were indicted in the scandal.