Sinclair may also face additional administrative penalties from the Army, which could force him to retire at reduced rank. That could cost Sinclair hundreds of thousands of dollars in pension benefits.
Retired Maj. Gen. Walt Huffman, a Texas Tech University law professor who previously served as the Army's top lawyer, said Sinclair could be busted back two ranks to lieutenant colonel since the affair at the heart of the case began before his most recent promotion.
Huffman said it's possible the judge could sentence Sinclair to a punishment lower than what's called for in the plea agreement.
"If the judge determines he was a good soldier who served his country well other than his inability to control his zipper, then the judge might cut him a break," Huffman said. "But either way, his career in the Army is going to be over."
Sinclair's new plea agreement was approved and signed over the weekend by a high-ranking general overseeing the case, according to a copy provided by the defense team.
The married 27-year Army veteran pleaded guilty earlier this month to having improper relationships with three subordinate officers, including the female captain who accused him of assault. He also pleaded guilty to adultery, which is a crime in the military.
Under the plea deal reached over the weekend, Sinclair also admits to abusing a government credit card he used while traveling to visit his mistress.
Defense attorney Richard Scheff said Sinclair is admitting to his mistakes, but added that the general is pleading guilty to behavior that likely wouldn't be criminal in the civilian world.
"After wasting millions of taxpayer dollars, the Army finally admitted what it's known for many months: General Sinclair is innocent of sexual assault," Scheff said. "Brigadier General Sinclair has admitted to mistakes that are normally a matter between husbands and wives, or employees and HR departments. It's time to put this matter to rest."