Gov. Chris Christie’s administration struck back hard and personally on Saturday against a former ally who accused the governor of lying about how much he knew about the lane closings at the George Washington Bridge, a scandal that has become the biggest crisis in Mr. Christie’s political career.

In a two-page memo obtained by Politico, which it said was sent “from the governor’s office,” David Wildstein, a former high-ranking official at the Port Authority of New York and New Jersey, was portrayed as a loose cannon who was attacking Mr. Christie only in an effort to save himself and noted that he had been described in newspaper accounts in the past as “tumultuous” and someone “who made moves that were not productive.”

The memo listed five incidents as evidence, saying that “as a 16-year-old kid,” Mr. Wildstein had sued over a school board election; that he had been “publicly accused by his high school social studies teacher of deceptive behavior”; that he had a controversial tenure as mayor of Livingston, N.J.; that he had been an anonymous blogger; and that he “had a strange habit of registering web addresses for other people’s names without telling them.”

The memo, which Politico said was sent to friends and allies, went on to attack Mr. Wildstein for ulterior motives in his accusation against the governor on Friday, noting that he has been seeking immunity from prosecutors in the federal investigation into the lane closings in September, and that he wanted the Port Authority to pay his legal bills.