Jeh Johnson, the Pentagon's top lawyer, notified Bissonnette last Thursday that the Pentagon believes he is in "material breach and violation" of two nondisclosure agreements and of a related document he signed upon leaving active duty in April 2012.
In response, Robert D. Luskin of the law firm Patton Boggs wrote to Johnson on Friday that his firm is representing Bissonnette and asserting that he is not in breach of his nondisclosure agreements.
The Justice Department could go after the profits of the book in a civil proceeding if it is determined that he violated the nondisclosure agreement by not getting the book pre-cleared.
Associated Press National Security Writer Robert Burns contributed to this report.
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