SO CONVINCED is Manhattan District Attorney Cyrus R. Vance Jr. (D) of the importance of rape kits in improving public safety that he is dedicating $35 million to help eliminate the backlog that has become a national disgrace. The money is the single largest financial contribution toward testing the hundreds of thousands of rape kits that have sat — for years and even decades — untouched in police storage facilities.

But for the effort to have maximum impact, Congress must act to help local communities investigate and prosecute cases as well as put in place reforms to prevent backlogs from occurring again. Bipartisan agreement exists on this issue, so we hope Mr. Vance’s effort is a spur to the lame-duck Congress.

Under the program announced in New York on Wednesday, $35 million in civil forfeiture assets will be made available to localities and states across the country to test some 70,000 rape kits, which are a collection of physical evidence painstakingly taken from victims of sexual assault. New York has been a leader in processing untested kits, and Mr. Vance spoke of their efficacy in solving old crimes and preventing new ones. “Some of these people are serial offenders,” he said, and that “could lead to solutions of crimes all over the country.” The program will be run with the help of the Joyful Heart Foundation, a victims’ advocacy organization that has focused attention on the ramifications of untested rape kits and the need for urgency in solving the problem.

Testing the kits — a process costing between $500 and $1,000 — is only the first step. Additional resources are needed to conduct investigations, bring perpetrators to justice, reach out to neglected survivors and build systems to prevent future backlogs. President Obama has proposed a new federal grant program to help communities undertake this work, and both the House and the Senate Appropriations Committee have included $41 million for this effort in their appropriations bills for fiscal 2015. But the proposal has been caught up in Congress’s uncertainty over the budget.

Congress should keep in mind the words of Mariska Hargitay, the actress who founded Joyful Heart: “Testing rape kits sends a fundamental and crucial message to victims of sexual violence: You matter. What happened to you matters. Your cases matter. Not testing kits sends the opposite message.”