(CNN) - A federal investigator tried contacting a former top deputy to Gov. Chris Christie as well as members of her family as part of its investigation into a political scandal roiling his administration, court papers showed on Thursday.
It is the second time this week that U.S. Attorney Paul Fishman's office has been shown to be on the ground actively probing suggestions that top Christie appointees orchestrated traffic jams near the George Washington Bridge in Fort Lee last year to politically punish that town's mayor for not endorsing the governor for reelection.
An attorney for Bridget Kelly, a former Christie deputy chief of staff who was fired over scandal developments, said in court papers filed on Thursday that an investigator from Fishman's office "attempted to contact Kelly, her parents, her ex-husband and other in-laws to ask questions about Ms. Kelly" on January 10.
They all refused to speak to the agent.
An attorney for Bill Stepien, Christie's former campaign manager, said earlier this week that the FBI had visited his home and questioned people who know him around the same time, according to a separate court filing.
Both Kelly and Stepien are fighting subpoenas from a state legislative committee also investigating the scandal that has called into question Christie's forceful governing style and clouded prospects for a potential presidential campaign in 2016.
The investigative committee has asked Kelly and Stepien, who Christie asked to leave his political organization in January, to submit emails, texts and other documents.
Kelly's attorney, Michael Critchley, wrote in the 43-page brief filed in Mercer County Superior Court that the act of complying with the state subpoena "has a potentially incriminating" aspect.
He argues she is the subject of a criminal investigation and the Fifth Amendment is meant to protect people in her situation.
Critchley says Kelly is being asked to produce highly personal and potentially privileged information that would also violate her Fourth Amendment rights, if she were to comply.
Stepien's lawyer made a similar argument in his court submission.
A court date has been set for March 11, when a judge may rule on their cases.
Christie has said he didn't find out about the traffic mess until after it happened, and has stressed he knew nothing about any related political mischief.
He has not been subpoenaed as part of the dual investigation but his office has, and Christie says the administration is complying.
CNN's Shimon Prokupecz contributed to this report.