As ProPublica reported this fall, the Obama administration is rolling back limits on some U.S. arms exports. Experts are concerned that the changes could result in military parts flowing more freely to the world’s conflict zones, and that arms sanctions against Iran and other countries will be harder to enforce.

Now, some in Congress are seeking to add back some oversight mechanisms lost in the overhaul – over opposition from the administration.

As part of the administration’s larger changes to what many view as an antiquated arms export system, thousands of military items have moved out from under the State Department’s long-standing oversight to the looser controls of the Commerce Department.

Commerce Department officials have said that, as a matter of policy, they will continue human rights vetting of recipient countries and reporting big sales to Congress, things the State Department was legally required to do.

A bill introduced in the House Foreign Affairs Committee last month would add back those and other legal requirements for many military items moving to Commerce control.

The bill is intended to “preserve Congressional oversight of arms transfers as the administration implements its Export Control Reform Initiative,” said Daniel Harsha, a spokesman for the committee.

While administration officials declined to comment on the pending legislation, they have quietly resisted it.

“They’ve opposed it because they don’t think it’s necessary,” said Colby Goodman, a consultant to the Open Society Policy Center who was formerly with the U.N. Office for Disarmament Affairs. (Open Society provides funding to ProPublica.) “The administration appears to prefer having human rights vetting in policy only. Unfortunately, this stance makes it easier for the administration to ignore such vetting when it suits them.”

Brandt Pasco, a lawyer who helped craft the overall export changes, said Congress may be over-reacting. “Most of what’s being transferred over, the reason it was being moved to the Commerce system was that it was not seen as being enormously sensitive,” said Pasco, who added that the human rights requirement risked creating “needless bureaucracy” for unimportant items.

The Senate is also considering legislation in response to the changes, though its approach may have less practical effect than that of the House.

The president decides what stays on the State Department’s control list, and the current standard is items that provide a critical military advantage to the U.S. Sen. Robert Menendez, D-N.J., has put forward an amendment to the annual defense spending bill that lays out broader criteria for the president’s decision.

The amendment says that the State Department should continue to have tighter control over exports of equipment that could provide “substantial military or intelligence capability” to the foes of the U.S. or its allies.

Brittany Benowitz, who was a defense adviser to former Sen. Russ Feingold, D-Wisc., and is the co-author of a paper on the export changes, said that the administration’s standard was too narrow. “The export control criteria are focused on sophisticated technologies that foreign militaries are trying to obtain, but in this day and age, the U.S. faces threats from not-so-sophisticated, often non-state actors,” she said.

The amendment, however, ultimately leaves the decision to move equipment off the State Department’s list to the president’s judgment.

“If what the administration is saying is true, that the reform is moving relatively minor parts and components [to Commerce], then they shouldn’t have a problem with the amendment,” said Goodman, the Open Society consultant.

The approach of both the House and Senate line up with recommendations made by the American Bar Association’s Center for Human Rights in a white paper published in January, which called on Congress to patch regulatory gaps opened up by the shift to Commerce.

The immediate future of either effort isn’t clear, given the packed legislative agenda squeezed into the end of the year.

The administration has said its changes to arms export rules are a necessary update to an outdated oversight system. By loosening controls on “items that pose a low risk to national security,” officials at the State and Commerce Departments told ProPublica, the government can “improve its ability to safeguard those items that most require protection.”

Defense manufacturers have pushed for the rule changes, which they believe will boost their competitiveness overseas. The Defense Department has also said that the changes will make it easier to equip allies.