The U.S. House of Representatives passed legislation on Tuesday that would made permanent a five-year-old law that has allowed the secretary of education to excuse members of the armed forces from their federal student-loan obligations while they are on active duty.

The bill, HR 3625, which does not yet have a counterpart in the Senate, would also encourage colleges to refund tuition and fees to students who are called to active duty while enrolled, and to make it easier for such students to re-enroll upon their return.

The bill’s sponsor, Rep. John Kline, a Republican of Minnesota, said that permanently extending the law would “show Congress’s commitment to our troops, our students, and our schools.”

But it’s unclear how important the law has been to student-soldiers since it was first enacted, in 2001. The Education Department has not conducted a study of the program’s effects that Congress requested, and the department told the Government Accountability Office last fall that it had no intention of doing so. In a letter to the office included in a GAO report issued last November, the department said that it could not conduct the study because it lacked a mechanism for identifying beneficiaries of the act, and upgrading its data systems to collect those data would require a “rigorous” and “costly” process.

A department spokeswoman said the agency was “continuing to try to design a study that would meet the needs of policy makers, including members of Congress, without obtaining personally identifiable information about members of the armed forces who are deployed to military service overseas.” —Kelly Field