While Mr. Christie was in Virginia on Friday morning talking about the need for trust and truth in government, Mr. Wildstein was in federal court in Newark pleading guilty to charges of conspiracy to commit fraud and “conspiracy against civil rights” of residents caught in the traffic jam.

Image David Wildstein Credit... Kirsten Luce for The New York Times

A short time later, Bridget Anne Kelly, Mr. Christie’s former deputy chief of staff, and Bill Baroni, who was the deputy executive director of the Port Authority, were indicted by the United States attorney for New Jersey, Paul Fishman. Ms. Kelly and Mr. Baroni face nine counts, including conspiracy to misuse property receiving federal benefits, commit wire fraud and deprive citizens of civil rights by engineering the traffic nightmare as political payback to Mayor Sokolich for failing to endorse Mr. Christie in his 2013 re-election campaign.

Mr. Wildstein acknowledged in court what many had assumed to be true all along: that he had worked with Mr. Baroni and Ms. Kelly to shut down sections of the bridge, causing huge traffic jams, as an act of political revenge. Mr. Wildstein said that the threesome also agreed to concoct a phony traffic study as a cover story.

Ms. Kelly read a statement denying the charges and calling Mr. Wildstein a liar. She also said that it was “ludicrous” to assume she was the only member of the governor’s staff who knew about the bridge caper. Mr. Baroni denied the charges through his lawyer and also said Mr. Wildstein was lying.

Mr. Fishman said Friday that no further charges were expected concerning the bridge scheme. Still, many important questions are yet to be answered, especially about other suspicious dealings of senior officials at the dysfunctional and patronage-riddled Port Authority. One is whether David Samson, Mr. Christie’s close friend, misused his position as former chairman of the authority for personal or professional gain. In one case, as United Airlines was angling for improvement in its terminal, which is overseen by the authority, the airline began scheduling a flight from Newark to a city close to Mr. Samson’s weekend home in South Carolina.