(CNN) -- A former Navy SEAL did not violate military secrecy agreements or break federal law by writing a book about the raid last year that killed al Qaeda leader Osama bin Laden, the author's lawyer said Friday.
In a letter to Defense Department General Counsel Jeh Charles Johnson, Robert Luskin of Patton Boggs in Washington said "Mark Owen," the pen name of author Matt Bissonnette, "remains confident that he has faithfully fulfilled his duty" not to disclose classified information.
"Mr. Owen is proud of his service and respectful of his obligations. But he has earned the right to tell his story; his abiding interest is to ensure that he is permitted to tell it while recognizing the letter and spirit of the law and his contractual undertakings," Luskin said.
Johnson, the military's top lawyer, warned the author on Thursday that he had violated secrecy agreements and broke the law with "No Easy Day." Johnson said the military was considering pursuing "all remedies legally available" against the former SEAL and his publisher, Penguin Putnam.
"In the judgment of the Department of Defense, you are in material breach and violation of the nondisclosure agreements you signed. Further public dissemination of your book will aggravate your breach and violation of your agreements," Johnson wrote in a letter to "Mark Owen."
The author feels his obligations to the military and former colleagues are "as important to him as any mission he undertook while on active duty," and sought legal advice before publishing the book "to ensure that it did not disclose any material that would breach his agreements or put his former comrades at risk," Luskin's letter said.
The Pentagon's classified information, nondisclosure agreement "invites" but doesn't require Bissonnette to submit his book for pre-publication review, the lawyer's letter said.
The Pentagon's "sensitive compartmented information nondisclosure statement" does require pre-publication security review in cases involving specific "special access programs," but Bissonnette's book does not violate that statement either, Luskin said.
"Accordingly, it is difficult to understand how the matter that is the subject of Mr. Owen's book could conceivably be encompassed by the non-disclosure agreement that you have identified," the lawyer wrote.
The book is a gripping account of the May 2011 SEAL raid on bin Laden's compound in Abbottabad, Pakistan.
The story sheds more light on the now famous skill and daring of the SEALs. But the book's existence stoked controversy because members of the elite unit do not usually divulge details of their operations.
CNN obtained a copy of the book, which will officially be released September 4.
In it, Bissonnette recounts the raid in detail, including the following sequence that occurred inside the compound:
Bissonnette wrote that he was part of a team heading up a stairwell in search of bin Laden, forces led by a SEAL point man.
"We were less than five steps from getting to the top when I heard suppressed shots.
"The point man had seen a man peeking out of the door on the right side of the hallway about 10 feet in front of him. I couldn't tell from my position if the rounds hit the target or not. The man disappeared into the dark room."
The man who peeked out the door had been shot, but was still moving when the SEALs entered the room. Bissonnette described the end.
"In his death throes, he was still twitching and convulsing. Another assaulter and I trained our lasers on his chest and fired several rounds. The bullets tore into him, slamming his body into the floor until he was motionless."
The book is one of several about the operation to have surfaced.
Government officials only recently became aware that the former SEAL was writing a book, but they were told it encompassed more than just the raid and included vignettes from training and other missions.
They wanted to see a copy, a Defense Department official said, to make sure no classified information would be released and to see if it contained anything that might identify other team members. Johnson's letter to Bissonnette came after that review.
CNN's Barbara Starr and Joe Sterling contributed to this report.