Gov. Chris Christie of New Jersey lied to reporters when he said he did not believe any senior member of his staff knew about the plot to block traffic to the George Washington Bridge, one of his aides told a colleague in a text message included in a federal court filing on Wednesday.

“Are you listening?” the aide, Christina Genovese Renna, texted a colleague while Mr. Christie spoke at a news conference. “He just flat out lied,” Ms. Renna wrote. Then she added that if certain emails were discovered, “it could be bad.”

Ms. Renna’s text exchange, submitted as part of a filing in United States District Court in Newark, is the first piece of evidence to surface that suggests that Mr. Christie may have known more about the scheme than he has admitted.

A former ally of the governor, David Wildstein, who pleaded guilty to two counts of conspiracy in the case, has contended that evidence exists to show that Mr. Christie knew about the plot as it was being carried out. But Ms. Renna is the first former member of Mr. Christie’s staff to accuse him of lying about the matter.