After an investigation - by a law firm hired by the state at taxpayer expense - reported that Chris Christie had no role in the Bridgegate scandal, the governor took off for an interview with Diane Sawyer and then flew to Las Vegas to speak to the Republican Jewish Coalition.

It was all a carefully orchestrated public-relations blitz. But virtually no one bought it. According to a Rutgers-Eagleton poll released last week, 49 percent of voters said they did not believe "at all" that Christie had no role in closing lanes, apparently as political retaliation, on the George Washington Bridge.

The report by the Los Angeles law firm Gibson Dunn & Crutcher, which is billing taxpayers $650 an hour, was a laughable whitewash. Key players in the lane closings - including close Christie ally and former Port Authority of New York and New Jersey chairman David Samson - were not interviewed. Apparently no audio or visual recordings or stenographic transcripts of the interviews were made. Nor were the interviews conducted under oath.

And this "investigation" is expected to cost at least $1 million.

Which raises an obvious question: Why are taxpayers footing the bill for this sham?

Christie's political donors or the New Jersey Republican State Committee should be paying for this politically motivated Bridgegate review.

Christie had to know it wouldn't play in New Jersey, where the Legislature is investigating the lane closings and the U.S. Attorney's Office has convened a grand jury to investigate the lane closings and Hoboken Mayor Dawn Zimmer's claim that the Christie administration tied Sandy aid to approval of a controversial development project.

But that wasn't the point. This was all about a national PR blitz and keeping Christie's presidential chances alive.

Technically, Gibson Dunn was hired by the state Attorney General's Office. But as reporter Matt Katz noted on, attorney Randy Mastro's release of the report appeared to be carefully coordinated with the Governor's Office, with two Christie aides present at the press conference.

And in addition to all this, the report went out of its way to paint former Christie aide Bridget Anne Kelly, who played a key role in the lane closings, as an emotionally distraught, jilted lover of Christie campaign manager Bill Stepien.

You are paying for this nonsense. But you shouldn't be. The Gibson Dunn report doesn't come close to passing the sniff test.