Credit: Susan Walsh/AP Photo

The Senate Armed Services Committee has voted against Sen. Kirsten Gillibrand's bill that would have taken military commanders out of the process of reviewing sexual assault cases.

Instead, the committee voted for an alternative proposal by Sen. Carl Levin, D-Mich., calling for automatic reviews of a commander's decision not to prosecute a sexual assault case.

Last week, the Joint Chiefs of Staff came out against the proposal by Gillibrand, D-N.Y., saying it would undermine good order and discipline.

Earlier Wednesday, Defense Secretary Chuck Hagel told the Senate Budget Committee that he was opposed to the legislation.

Hagel said he is a firm believer in accountability and, "if you don't hold people accountable then you're not going to fix the problem. You can pass all the laws you want and that isn't going to work."

On Wednesday, Gillibrand made impassioned pleas in favor of her bill at Wednesday's mark-up of the National Defense Authorization Act. She told members of the committee that victims have repeatedly said that they fear retaliation in their units if they report a sexual assault.

"So we can believe them or we cannot believe them," Gillibrand said. "Many here don't believe the victims, they don't believe the victims. They don't' believe chain of command is the problem. I urge support of our original markup."

Sen. Tim Kaine, D-Va., responded by saying everyone on the committee "believes the victims. … I don't think that distinguishes anyone on this committee from each other. "

Kaine added, "When our heroes have this problem that is so serious, it's not just a stain on our military, it's a stain on our country."

Though her bill eventually was defeated 17-9, one of the bill's supporters, Sen. Ted Cruz, R-Texas, said he'd changed his vote as a result of Gillibrand's arguments.

He said he was swayed by her arguments that removing commanders from the process in the British and Israeli militaries had led to an increase in reporting of sexual assault cases. He suggested that if Levin's amendment passed and the level of reporting remains "abysmal," then Gillibrand's proposal should be revisited.

But even some of the most outspoken critics of sexual assault in the military said they could not vote for Gillibrand's legislation.

Sen. Claire McCaskill, D-Mo., a former prosecutor, said she respected Gililbrand "with all of my heart" and wanted to do away with sexual assault in the military but she said she couldn't vote for Gillibrand's bill.

She pointed out that military commanders will often proceed with a criminal case where civilian prosecutors might not because of the of the "he said-she said" nature of cases. She added that there was not any data to support the assertion that removing commanders from sexual assault cases is going to have a positive impact on retaliation in units.

However, McCaskill said she agreed with Gillibrand on one thing: "We are not going to give up focusing on this problem. We aren't going anywhere."

She cautioned military leaders against thinking that the debate over sexual assault would end with congressional votes.

"This has just begun," she said, warning senior commanders that Congress would "hold your feet to the fire."