New Jersey taxpayers have been billed more than $10 million for legal services performed for Gov. Chris Christie’s administration in the George Washington Bridge lane closure case, including more than $2 million by a firm that the governor’s 2013 re-election campaign still owes money.

Invoices released by the state attorney general’s office Friday evening show the governor’s office spent $2.3 million on digital forensics firm Stroz Friedberg in 2014 and 2015. That’s in addition to the $8 million Christie’s administration spent through December for services from the Gibson, Dunn & Crutcher firm.

Christie’s 2013 gubernatorial campaign used Stroz Friedberg to respond to subpoenas from the U.S. Attorney’s Office. It still owes the firm nearly $362,000, according to a campaign filing made last month. The firm began charging the state for work in January 2014 after Christie began his second term, according to invoices released Friday. It’s the first time the Stroz Friedberg expenses have been publicly disclosed.

Two former Christie allies, Bill Baroni and Bridget Kelly, have pleaded not guilty to federal charges that they concocted a scheme to partially close the bridge as political payback to a New Jersey mayor who wouldn’t support Christie’s re-election effort. Former Port Authority of New York and New Jersey official David Wildstein pleaded guilty. Christie, who ended his 2016 presidential campaign this month, has repeatedly denied any prior knowledge of the scheme, and a taxpayer-funded report he commissioned absolved him of wrongdoing.

Leland Moore, a spokesman for the attorney general’s office, said the governor’s office is using Stroz Friedberg “because of the wide-ranging subpoenas it received from the Legislature and the United States Attorney’s Office and the many different systems and devices from which potentially responsive documents had to be gathered.”

Christie’s 2013 campaign treasurer, Ron Gravino, confirmed in an email that the debt is outstanding and said state election law prohibits it from being forgiven. The campaign also owes more than $600,000 to Newark-firm Patton Boggs, according to the campaign filing.

The state’s Election Law Enforcement Commission granted a request from the campaign in February 2014 to be allowed to continue raising money to answer the subpoenas. Mark Sheridan, a Patton Boggs attorney who represented the campaign in that request, wasn’t immediately available to comment.

Lawyers for Baroni and Kelly have argued in court over the level of information they said they’ve received in the case. A federal judge this month granted them the ability to subpoena Gibson Dunn for what they contend are thousands of pages of relevant documents, particularly communications between people in Christie’s office and the bridge’s operator during the September 2013 closures.

Gibson Dunn attorney Randy Mastro has said that the governor’s office didn’t withhold any documents related to the lane realignment, “so there are no other documents to produce in that regard.”

(AP)