"I don't want to get into any of the specifics as to what [the subpoena to the governor's office] will include or not include," Greenwald said.
He said the committee's actions "will be determined by the evidence that comes forward."
The subpoenas underscored how what began as a review of the operations of a transportation agency has metamorphosed into a full-scale investigation into the Christie administration's involvement in a scandal that imperils the popular Republican governor's political career.
The recipients are Christie's chief of staff, Kevin O'Dowd; communications director, Maria Comella; spokesmen Michael Drewniak and Colin Reed; chief counsel, Charles McKenna; director of the authorities unit, Regina Egea; and aides Evan Ridley and Christina Genovese.
Drewniak and Reed did not respond to a request for comment Friday.
Democrats confirmed Friday that the Assembly committee had also served a subpoena to Bridget Anne Kelly, the deputy chief of staff Christie fired last week after the disclosure of an e-mail she sent in August to a Port Authority official that read: "Time for some traffic problems in Fort Lee."
Subpoenas also were sent to Christie's former campaign manager and political adviser, Bill Stepien; Matt Mowers, Christie's former regional political director; David Samson, chairman of the Port Authority of New York and New Jersey's board of commissioners; and three other Port Authority officials.
Documents released last week by Assembly Democrats show correspondence between Christie aides and his former appointees at the Port Authority plotting to close lanes leading from Fort Lee to the bridge in an apparent act of political revenge against the borough's Democratic mayor, who did not endorse the governor's reelection.
Christie has denied involvement in or knowledge of the scheme.
Kelly sent the e-mail calling for traffic problems on Aug. 13 to David Wildstein, a Christie appointee at the Port Authority, who immediately replied: "Got it."
He and another Christie appointee at the Port Authority, former Republican State Sen. Bill Baroni, resigned last month. They, too, were served subpoenas Friday.
The documents disclosed last week - stemming from seven previous subpoenas of Port Authority officials - showed that a number of Christie's staff members, including Egea, whom Christie has tapped to become his new chief of staff, and Drewniak were notified of the traffic jams as early as September.
Christie has nominated his current chief of staff, O'Dowd, to be state attorney general.
Samson's name also appeared in the documents. After Patrick Foye, the executive director of the Port Authority who was appointed by Democratic New York Gov. Andrew Cuomo, halted the lane closures, Wildstein wrote to Kelly: "We are appropriately going nuts. Samson helping us to retaliate."
Text messages from early August included in the documents submitted by Wildstein refer to a meeting between Samson and Christie but do not indicate the topic or whether the meeting occurred.
Wildstein refused to answer questions during a hearing before lawmakers last week. On Friday, his lawyer told the Associated Press that if he received immunity, "he'll talk."
A spokeswoman for the U.S. Attorney's Office in New Jersey said Friday that the office was continuing to review the case and could not comment on decisions to grant immunity.
The Assembly committee, which was formed Thursday, also issued a subpoena to Christie's campaign committee and a former member.
The subpoenas seek correspondence and documents from Sept. 1, 2012, to the present related to the lane closures. Responses are due by Feb. 3.
A Senate committee also formed Thursday plans to meet next week to issue subpoenas in the matter.
On Thursday, the governor's office announced the retention of Randy Mastro, a former federal prosecutor and deputy to then-New York Mayor Rudy Giuliani, and his firm, Gibson, Dunn & Crutcher L.L.P., as outside counsel.
The firm is also representing the Port Authority in a lawsuit filed by the AAA, and has represented the agency in another investigation by Assembly lawmakers into toll increases.
Mastro did not return an e-mail seeking comment Friday.