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Defense Secretary Chuck Hagel says he is ordering a review of the rules that allow a military commander to overrule court martial convictions by military juries. Hagel wrote a letter to Sen. Barbara Boxer, D-Calif., which is posted on her website.

The move was prompted by the outrage on Capitol Hill after an Air Force general decided to throw out an F-16 fighter pilot's jury conviction for aggravated sexual assault. Lt. Col. James Wilkerson was convicted of the assault, which took place at his home base in Aviano, Italy where he was the base's Inspector General. Lt. Gen. Craig Franklin threw out the conviction, reinstated him in the Air Force and cleared his record.

Franklin made the change against the recommendation of his staff lawyer and instead agreed with Wilkerson's attorney that prosecutors had not proved that he was guilty beyond a reasonable doubt.

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Wilkerson was able to do this because he was designated the "convening authority" for the case. Under the Uniform Code of Military Justice (UCMJ), convictions go to the case's convening authority, a commander, for final action. This happens in every military trial.

"I believe this case does raise a significant question whether it is necessary or appropriate to place the convening authority in the position of having the responsibility to review the findings and sentence of a court-martial," wrote Hagel, "particularly prior to the robust appellate process made available by the UCMJ."

Hagel can't review the actions of the Wilkerson case or overturn the case, but he's ordering a review of the case to see whether it "points to changes that should be considered in the UCMJ, or in the military services' implementation of the UCMJ and, if so, what changes should be made."

The Wilkerson case has gained traction over the past week on Capitol Hill as Democratic Senators Boxer, Claire McCaskill and Debbie Stabenow have all expressed outrage over the general's actions. They demanded that the military change the UCMJ provisions to remove the leeway commanders have in sexual assault cases. McCaskill has a meeting set up with the Air Force's top general, Chief of Staff Gen. Mark Welsh.

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On Tuesday Rep. Jackie Speier, D-Calif, is expected to introduce legislation in the House that, if enacted, would remove the ability of military commanders to unilaterally overturn or lessen the decisions of judges or juries at courts martial under their review. But at meeting of the Senate Armed Services Committee last week, the commander of the U.S. Central Command said that while he wasn't aware of the Wilkerson case, he stood by the military legal system in its current form.

Marine Gen. James Mattis said the powers bestowed upon convening authorities were intended to serve as a defendant's right and check to the jury system.

"No court system is more subject to being characterized as a kangaroo court than one where military officers who are in command also initiate it," Mattis said, adding he believed the U.S. Military Justice code "overwhelmingly" served justice.

"I say that because as a commander, I was not just responsible for prosecution; I was also responsible for defense," he said. "And commanders must balance both of those if we're to have a fair system."

On Wednesday the case is expected to be discussed at the first Senate hearing in a decade dedicated to the issue of sexual assault in the military.