TRENTON — New Jersey taxpayers have been billed $6.52 million so far this year by Gov. Chris Christie's private attorneys dealing with the aftermath of the George Washington Bridge scandal, according to invoices released today by acting state Attorney General John Hoffman.

Lawyers at Gibson Dunn & Crutcher billed $3.26 million in March and April, the invoices show. They also billed $3.26 million in January and February, according to previous invoices. At $650 an hour, the firm's rate is a steep discount, it says.

With ongoing state and federal investigations into the massive traffic jam at the foot of the world’s busiest bridge last year, Gibson Dunn and other law firms may still be billing for work beyond April.

The governor retained Gibson Dunn, which is based in Los Angeles and has offices in New York, to investigate claims that his top aides and associates closed down two of New Jersey’s local-access lanes to the George Washington Bridge last year, snarling traffic and delaying emergency responders in the borough of Fort Lee from Sept. 9 to 13.

After more than 70 interviews with Christie and his team, lead attorney Randy Mastro released a report in March that cleared the governor of any wrongdoing. Democrats have criticized the Mastro report as a "whitewash," noting that Gibson Dunn lawyers did not interview many of the key players involved in the scandal or staff at the Port Authority of New York and New Jersey, which manages the bridge.

The March report laid the blame for the scandal on Christie’s former deputy chief of staff, Bridget Anne Kelly, and on David Wildstein. Attorneys for both have disputed the Mastro report’s findings.

"They were very well paid to do a whitewash of the governor’s office, which was not worth the paper it was written on," said Senate Majority Leader Loretta Weinberg (D-Bergen), co-chair of a special legislative committee investigating the lane closures. "It was a report that came to a conclusion without ever talking to any of the named players and without talking to anybody at the Port Authority."

Mastro’s team added that there could be more revelations as separate inquires by the state Legislature and U.S. Attorney Paul Fishman, the top federal prosecutor in New Jersey, continue.

Gibson Dunn also investigated claims made by Hoboken’s Democratic mayor, Dawn Zimmer, that top Christie administration officials held hostage federal disaster-relief funds while they pressured her to approve a waterfront development. Zimmer’s claims are baseless, according to the Gibson Dunn review.

Christie, who is mulling a run at the White House in 2016, has defended the Mastro report as "comprehensive and exhaustive."

"It’s an exhaustive report that follows the mandate that I set out when I commissioned the review," Christie said at a news conference in March, thanking Mastro. "I told him to go find the truth no matter where it led."

But Christie conceded the report could have some gaps. "It will be tested by the other investigations that are ongoing," he said.

Christie’s lawyers also billed the state in connection with the state Legislature’s investigation of the bridge scandal. Attorneys at the firm helped respond to subpoenas or review other documents connected to the legislative probe.

Weinberg said she did not know how much of Gibson Dunn’s billings were related to her committee’s investigation. She added: "I know the first half of it was not well spent. They seem to be making a career out of public billing."

Several individual public employees or former workers are also billing the state in connection with Bridgegate subpoenas and legal inquiries, including members of Christie’s office.

The law firm Riker Danzig, based in Morristown, represents 17 of the staffers. It has billed the state $272,654, the invoices show. Attorney General Hoffman has declined to name the current and former state employees who are getting public dollars to pay for their private attorneys.

State Democrats have also retained outside counsel to help run their investigation. The latest tally of legal bills for the legislative committee showed they totaled $725,000 through the end of March.

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