Sen. Kirsten Gillibrand’s Military Justice Improvement Act (MJIA), which would remove prosecution of sexual assault from the military chain of command, will not be included as an amendment to the 2014 defense spending bill.

Leadership of the House and Senate armed services committees struck a deal Monday to pass the National Defense Authorization Act (NDAA) through both chambers with no amendments. Because the House recesses at the end of this week, Congress ran out of time to vote on amendments and still pass the NDAA by the end of the year. The defense bill has passed every year for the last five decades, and failure to do so is widely considered to be unthinkable, especially in an election year.

A vote had been expected on the MJIA and other amendments before the Thanksgiving recess, but a Republican filibuster delayed that process.

Gillibrand (D-NY) has tirelessly advocated to pass the MJIA as an amendment to the NDAA, and was confident about reaching the 60 votes required to break a possible filibuster. Her supporters included unusual allies such as Sens. Rand Paul (R-KY) and Ted Cruz (R-TX).

“Congress has chosen to sidestep the most important military justice reform to come across its desk in history, once again leaving sexual assault victims devastated and betrayed by inaction,” said Anu Bhagwati, Service Women’s Action Network (SWAN) executive director and former Marine Corps captain, in a statement.

But Gillibrand has also introduced the MJIA as a stand-alone bill and says she will continue to fight for its passage. Staff are confident that the bill will receive a vote.

SWAN policy director and former Marine Greg Jacob told Rewire that while it’s a “missed opportunity” for Congress not to vote on the MJIA now, the NDAA as it stands still provides important protections for sexual assault victims. Pre-trial hearings will be less adversarial and stressful for the victim, commanders will no longer be able to overturn sentences, and mandatory minimum sentences will be established for sexual assault.

But Jacob said his experience as a Marine officer taught him that the MJIA is necessary if the prosecution of military sexual assault cases is to be handled professionally.

“When I became an officer, suddenly I was supposed to be a legal expert and make decisions that affect the lives of my troops,” Jacob said. “It’s a serious decision to charge someone with a crime, and it should be handled by serious people who are trained to do what they do.”