Government watchdogs assailed the state Inspector General’s review of the leak scandal surrounding Gov. Andrew Cuomo as a mere ‘box-checking’ exercise, as the battered agency provided the first details of its review into the explosive allegations.

In a three-page letter released Wednesday under intense pressure from news outlets including The Post, the IG describes how its office handled a whistleblower claims that Cuomo obtained confidential information about a possible investigation into his onetime top aide — the now-imprisoned Joe Percoco.

“It looks like a check-the-box kind of investigation, they said, ‘we did something so we can say that we did something,’” Sen. Rob Orrt, a Republican, told The Post.

A former appointee to the state’s Joint Commission on Public Ethics, Julie Garcia, filed the whistleblower complaint that triggered the IG’s review in January.

She alleged Cuomo improperly obtained the information about a JCOPE vote to potentially probe Percoco and then contacted the man who appointed her, Assembly Speaker Carl Heastie, to complain.

“We need an independent investigation into who leaked the vote, not by an office in which the inspector general is appointed by the governor,” said an outraged Alex Camarda, an open government expert with the liberal group, Reinvent Albany.

The IG’s summary of its investigation claims that investigators performed “interviews, document review and analyses” and “solicited affirmations under penalty of perjury from JCOPE staff and commissioners in attendance” that they “did not disclose the information.”

Then, it goes on to say the whistleblower complaint contained “no supporting facts” and said the IG’s staff found “no individual was able to provide firsthand knowledge of any leak or potential perpetrator.”

It did not mention either Cuomo or Heastie as part of the nine-month probe, which experts said is essential to any thorough review.

“It’s laughable,” said Cam Macdonald, who leads the conservative Government Justice Center. “In what world would anyone think that in chasing down a leak an investigator would not interview the recipient of the leak?”

The IG’s office released the letter the day before Thanksgiving in response to Freedom of Information Law requests made by The Post and other media organizations in the state Capitol press corps.

Cuomo seemingly confirmed to reporters on Long Island that he received the information Tuesday when he said “never had an inappropriate conversation about JCOPE” and then argued there is nothing “legally” wrong about receiving leaked information.

“The only legal obligation is on the commissioners not to disclose, that’s why they talked to the commissioners because the commissioners are the only ones who have a legal obligation,” he added. “If a commissioner called you or someone else and told you something, you could tell whoever you want so the IG talked to the people who had the legal obligation.”

Cuomo’s staff delayed providing the tape of the remarks to reporters in Albany for hours in an apparent but futile bid to limit the fallout

Ethics experts blasted the governor’s argument Wednesday.

“Nobody from the administration filed a complaint and that’s what should’ve been done if, in fact, they found out about it,” said Blair Horner, who heads the New York Public Interest Research Group and was once a Cuomo staffer. “If someone in the executive or legislative branch hears information they should file a complaint, and that’s what Garcia did.”

Cuomo’s office denied the allegations and said the governor or his staff were never informed about JCOPE’s Percoco deliberations