A Navy SEAL is shown here at sunset. (Photo released by the U.S. Navy)

The Justice Department has dropped a second criminal investigation into Matt Bissonnette, the former Navy SEAL who helped kill Osama bin Laden in May 2011 and later wrote a best-selling book about the secret operation.

Federal prosecutors had been scrutinizing consulting work that Bissonnette had done while still on active duty as a SEAL and whether it violated conflict of interest laws, said his attorney, Robert D. Luskin. He served in SEAL Team 6, known in the military as U.S. Naval Special Warfare Development Group, or DEVGRU.

Luskin said the prosecutors in the Eastern District of Virginia (EDVA) agreed in April they would not prosecute Bissonnette.

“We ultimately agreed it wasn’t criminal,” Luskin said.

A spokesperson for EDVA declined to comment.

"No Easy Day: The Firsthand Account of the Mission that Killed Osama Bin Laden," by Mark Owen with Kevin Maurer. (AP Photo/Dutton) “No Easy Day: The Firsthand Account of the Mission that Killed Osama Bin Laden,” by Mark Owen with Kevin Maurer. (AP Photo/Dutton)

In August 2015, federal prosecutors in southern California separately reached an agreement in which Bissonnette would not be charged for what they said was the unauthorized release of classified information in the book he wrote about killing the al-Qaeda leader. Bissonnette, who wrote the book under the pseudonym Mark Owen, failed to submit it to the government for review.

Instead, as part of a civil forfeiture, Bissonnette agreed to return the net proceeds he earned from the book, “No Easy Day: The Firsthand Account of the Mission That Killed Osama bin Laden.” He sold more than 1 million hard copies, according to a source in the publishing industry.

Bissonnette filed suit in New York against his onetime attorney, Kevin Podlaski, and his former firm Carson Boxberger, alleging that Podlaski, a former Army lawyer, had given him bad legal advice to not submit the book for review.

That suit was dismissed in 2015, but Bissonnette sued again in Indiana, where Podlaski had joined the firm Beers, Mallers, Backs & Salin. That case is still ongoing. Podlaski has denied Bissonnette’s allegation and said in legal filings that he appropriately advised the SEAL on how to handle non-disclosure agreements involving classified information.

Bissonnette’s Texas-based lawyer in that lawsuit, Randy Johnston, said Tuesday that his client would have to return about $8 million that he made from the sale of the book. Bissonnette’s total losses from the publishing of the book, including legal fees and lost income, could exceed $10 million, Johnston said.

Luskin said it is clear now that “No Easy Day” should have been submitted for review, but “Bissonnette did not behave in a way that warranted criminal charges.”

The deal that Bissonnette reached with prosecutors was delayed when investigators began looking at his consulting business. That investigation, first reported by the online publication the Intercept in January, was launched after Bissonnette turned over a hard drive as part of his agreement with the government that had a photograph of bin Laden’s corpse and information about Element Group, a Virginia Beach company that Bissonnette helped start.

Bissonnette’s company worked with at least one defense contractor that supplied the U.S. military and Bissonnette’s SEAL team, according to the Intercept report. The firm has since been shut down, but still has a website that advertises ties to companies that include Remington Arms and Atlantic Diving Supply Inc., both of which have provided equipment to U.S. Special Operations Command units, according to an online federal contracting database.

Luskin said he hopes to wrap up the civil agreement regarding the book’s profits in weeks. “There is nothing left to be negotiated,” he said.

Naval Special Warfare Command, which oversees the SEALs, has stressed since the release of Bissonnette’s book the need for its personnel to not be “selfish” and disclose military secrets, as one letter distributed in 2014 put it. The letter, by Rear Adm. Brian L. Losey, the outgoing commander of Naval Special Warfare Command, and Force Master Chief Michael L. Magaraci, the senior enlisted sailor in the command, said those who broke with that ethos would not be allowed to represent the SEALs.

“We do not abide willful or selfish disregard for our core values in return for public notoriety and financial gain, which only diminishes otherwise honorable service, courage and sacrifice,” the letter said.

Bissonnette published a second book in late 2014 called “No Hero: The Evolution of a Navy SEAL.” Unlike “No Easy Day,” it was submitted to the government for review before it was released. Bissonnette told The Post at the time in an interview that the Pentagon “redacted a lot of it,” and about half those redactions were eventually allowed on appeal.

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