New Jersey Governor Chris Christie held a press conference last Friday to announce the resignation of David Samson as chairman of the Port Authority of New York and New Jersey (PA). Samson is the latest and most important of Christie’s appointees to depart in the wake of the ongoing scandal involving traffic tie-ups on the George Washington Bridge six months ago.

Samson’s resignation came only one day after the release of a 360-page report on the bridge affair. The report was commissioned by Christie himself and completed in the relatively rapid period of 10 weeks under the supervision of Randy Mastro. Mastro, a top partner in the 1,000-lawyer firm Gibson Dunn and Crutcher, is a former deputy mayor of New York City under Rudolph Giuliani (a Republican ally of Christie) and before that a prosecutor under Giuliani when he was a US Attorney.

Christie continues to be dogged by the scandal, which stems from a phony traffic study that appears to have been orchestrated by some of the governor’s aides and appointees as a form of political revenge against the Democratic mayor of the town of Fort Lee, New Jersey for his refusal to back Christie’s bid for a second term last year.

Mastro’s report was immediately branded—by the New York Times, Washington Post and numerous other editorialists—as a transparent whitewash of the governor’s role. It was pointed out that well over $1 million in public funds had been spent on the report but that the 70 interviews on which it is based do not include any of the major figures in the affair, including David Wildstein, another Christie appointee to the Port Authority; Bridget Anne Kelly, his former deputy chief of staff; Samson himself; or former Christie campaign manager Bill Stepien.

Dawn Zimmer, the mayor of Hoboken, who has accused the Christie administration of threatening her with punishment for withholding support for his initiatives, declared, “Randy Mastro could have written his report the day he was hired and saved the taxpayers the million dollars in fees he billed in generating this one-sided whitewash.”

The report tried to pin responsibility for the affair entirely on Wildstein and Kelly. Wildstein resigned in December and Christie fired Kelly in January, after an August 2013 email surfaced in which she had told Wildstein, “Time for some traffic problems in Fort Lee,” giving the lie to Christie’s claims that his administration had had no involvement in the scandal.

Mastro, whose press conference performance on March 27 was compared to that of a defense attorney rather than an unbiased investigator, went through contortions to try to explain the motivations of both Wildstein and Kelly, while portraying the governor as a somewhat hapless bystander.

Wildstein told Christie’s press secretary last December that he had informed the governor about the traffic study, discussing it with him when the two saw each other at a September 11 memorial ceremony in Manhattan, in the midst of the traffic chaos caused by bridge lane closings.

The Mastro report tries to explain this away, lest anyone conclude that Christie knew about the problem and refused to stop it. The report states that “whatever brief exchange [Wildstein and Christie] had occurred in a public setting where they were surrounded by many, including other Port Authority officials, the governor’s wife, and a steady stream of spectators requesting photographs and handshakes with the governor. Not surprisingly, the governor has no recollection of such an exchange.”

Mastro’s report went on to suggest, without any other evidence, that an affair that had recently been broken off between Kelly and Stepien was somehow responsible for Kelly’s behavior. “Events in Kelly’s personal life may have had some bearing on her subjective motivations and state of mind,” the report said. Some of Kelly’s friends denounced this reference as demeaning. Her lawyer issued a statement referring to “venomous, gratuitous, and inappropriate sexist remarks concerning Ms. Kelly.”

The report, furthermore, never mentions directly that Samson himself refused to be interviewed. One of the emails that surfaced earlier referred to the Port Authority chief as having suggested “retaliation” when the bridge lanes were finally reopened last September 13. Samson’s role on the Port Authority is also being examined in connection with potentially bigger issues, including the awarding of $2.8 billion in construction contracts for work on other bridges under the PA’s jurisdiction, and the distribution of Hurricane Sandy relief funds.

No reference was made to any of this in Christie’s announcement of Samson’s departure. Instead the governor said that his man at the Port Authority was “74 years old and tired.” In a statement issued after the press conference, Samson said: “Over the past months, I have shared with the governor my desire to conclude my service to the Port Authority of New York and New Jersey. The timing is now right, and I am confident that the governor will put new leadership in place to address the many challenges ahead.”

The scandal has also focused additional attention on the Port Authority itself, the quasi-governmental agency that is jointly controlled by the governors of New York and New Jersey, with an annual budget that is larger than many states and the ability to dispense patronage and direct huge contracts toward favored firms.

The main investigations of the bridge scandal are continuing, including one being conducted by the New Jersey state legislature and another by the US Attorney’s office for New Jersey. This latter investigation is the one that could lead to criminal charges, and is also being carried out by the very same office that was headed by Christie himself before he became governor.

The ongoing probes and revelations are front-page news partly because of Christie’s position—at least until the scandal surfaced—as a prominent contender for the Republican presidential nomination in 2016. The moves over the past few days, including the release of the Mastro report and the resignation of Samson, are further attempts by Christie to manage the scandal and counter the perception in ruling class circles that he may be damaged goods as far as a possible presidential candidacy is concerned.

Christie traveled to Las Vegas immediately after last week’s back-to-back press conferences in order to appear before the right-wing Republican Jewish Coalition, alongside Wisconsin governor Scott Walker, former Florida governor Jeb Bush and Ohio governor John Kasich. On Thursday night he went before the television cameras once again, giving an interview to ABC’s Diane Sawyer in which he pleaded ignorance, welcomed the just-issued report, denied that it was a “whitewash,” and said that “his style” of government was not to blame for the scandal.