Investigators in the New Jersey state legislature sent out 20 subpoenas Thursday night regarding the bridge scandal surrounding Gov. Chris Christie’s (R) administration, many to his top staffers. 

Christie’s former deputy chief of staff, Bridget Anne Kelly, and his former campaign manager, Bill Stepien, both received subpoenas as expected, according to The Record

In all, 17 subpoenas were sent to individuals, while three were sent to organizations.

Christie fired Kelly after emails revealed she was involved in the closure of lanes on the George Washington Bridge last year that jammed traffic, in apparent retribution for a local mayor who refused to endorse the governor’s reelection. 

Stepien was asked to stop his consulting work with the Republican Governors Association, and his nomination to head the state Republican Party was withdrawn for his involvement. 

Other high-level officials in Christie’s administration have been compelled to testify as well, including his chief of staff, chief counsel, spokesman and director of communications, according to the newspaper. 

Investigators in the state legislature declined to release a full list Thursday until all parties had received the subpoenas. Christie is not among those compelled to testify. 

A port authority official, David Wildstein, who went before an investigative committee earlier this month about his involvement, was held in contempt after pleading the Fifth Amendment and declining to testify. 

Christie has apologized for the incident and has denied knowledge of his staffers’ involvement. 

He retained a private lawyer on Thursday to help comply with a U.S. attorney’s review, and to conduct an internal probe into the incident — but failed to mention the legislature’s investigation in the announcement.

Former federal prosecutor Randy Mastro will head Christie’s team. He formerly served as the deputy mayor of New York City under Rudy Giuliani and worked as a U.S. assistant attorney in the state. He has a background in organized crime cases.