Pentagon leaders signaled an openness Thursday to altering military rules that govern the prosecution of sexual assaults, as support builds behind congressional initiatives that would take those decisions out of the chain of command.

Gen. Mark A. Milley, chairman of the Joint Chiefs of Staff, said his decision to drop his opposition to changing the military’s system for prosecuting such crimes was based in part on data suggesting that 20,000 service members were sexually assaulted last year.

“We can’t tolerate that level of divisiveness in our force. These are blue-on-blue assaults,” he said. “It cannot stand. It has to be resolved. So, yes, my mind is very open.”

Milley spoke to reporters at the Pentagon alongside Defense Secretary Lloyd Austin as lawmakers seek to advance House and Senate proposals that would create a cadre of independent military lawyers tasked with deciding which sexual assault cases are tried in military courts, a responsibility that now falls to military commanders.

Critics say the current system creates conflicts of interest, undermines troops’ trust in the military judicial system and deters victims from reporting crimes. But military leaders have opposed such a change, saying commanders’ responsibility for the welfare of their troops is a central tenet of military life.

That position appears to have shifted after an independent committee appointed by Austin to examine the military’s long-standing problem with sexual harassment and assault recommended the change.

Milley cited studies showing that junior soldiers do not believe their chain of command can adequately deal with the problem.

“We the chain of command, we the generals and colonels, the captains and so on, we have lost the trust and confidence of those subordinates in our ability to deal with sexual assault. So we need to make a change,” he said.

“We haven’t moved the needle,” he added. “And that’s the bottom line.”

Austin, who retired in 2016 as a four-star general, said he had asked uniformed leaders to look at the commission’s recommendations but stopped short of saying he would endorse them.

“We’ve done things a certain way for a while,” he said. “I think we really need to kind of broaden our horizons and begin to look at things differently and be willing to take different paths to try to improve things.”

It’s unclear what actions Austin, as defense secretary, could take unilaterally. Officials have said such a move would likely require congressional action, but an explicit Pentagon endorsement could generate additional support among lawmakers.

Previous measures have limited the decisions to refer sexual assault and other serious crimes to senior commanders.

The officials also addressed the U.S. withdrawal from Afghanistan following President Biden’s decision to remove all American troops by Sept. 11, the 20th anniversary of the 2001 attacks that triggered the U.S. military involvement there.

Asked whether the United States would continue to provide air support to Afghan forces once the American ground presence is gone, Austin said the military would offer funding and logistical support from afar. He appeared to rule out routine U.S. air support and declined to say whether the U.S. military would get involved in the event of a Taliban assault on a major city. Even as Afghanistan has raced to scale up its air force in recent years, U.S. air support has remained a crucial factor in Afghan forces’ ability to respond to Taliban attacks.

Experts and former officials have warned that Afghan security forces may not be able to keep the Taliban at bay. Before Biden’s decision, Pentagon leaders, including Austin and Milley, expressed support for keeping some U.S. forces in Afghanistan, but the White House decided on a full withdrawal.

Milley said it was too soon to assess how the Afghan forces would fare.

“It’s not a foregone conclusion in my professional military estimate that the Taliban automatically win, that Kabul falls, all those kind of dire predictions,” he said. “There’s a significant military capability in the Afghan government, and we’re going to have to see how this plays out.”