If Congress has its way, the deadliest shooting spree in American history may actually result in a modest improvement to the federal database that screens out unwanted gun users.

But it seems likely that it also will permit the National Rifle Association, one of the savviest lobby groups in town, to advance its own agenda at the same time.

A bill scheduled for markup on Thursday in the Senate Judiciary Committee would allocate $375 million a year to states so that they can enter more criminal and mental health records into the National Instant Criminal Background Check System, an automated service that lists people who are prohibited from owning guns.

In Virginia, the system failed to detect that Seung-Hui Cho had been adjudicated by a state justice official as mentally ill. Cho purchased semi-automatic pistols and on April 16 killed 32 people at Virginia Tech before taking his own life.

But as Members pushed the bill through the House in June in a matter of days, new language was added that gave the NRA a piece of its wish list that the group has been looking for since the mid-1990s.

The language, which the bill’s sponsor, Rep. Carolyn McCarthy (D-N.Y.), agreed to accept, requires that states who accept the NICS funding also set up a process that would restore the rights of people previously banned from owning a weapon because of mental instability — provided they can prove they are no longer a threat.

(The restoration provision would not apply to people with prior felony convictions.)

But the issue has done more than provide a convenient platform for a long-standing NRA goal.

The bill also has exposed a rare fissure in a usually united gun control lobby. The Brady Campaign to Prevent Gun Violence supports the legislation, while the Coalition to Stop Gun Violence, the Violence Policy Center and the Legal Community Against Violence are unsatisfied, saying it has been unfairly manipulated to please the gun industry and will put weapons in the hands of the wrong people.

“Setting up the restorations program has nothing to do with the original stated purpose of the NICS bill,” said Ladd Everitt, communications director for the Coalition to Stop Gun Violence.

Rob Recklaus, McCarthy’s chief of staff, conceded that the language was not in similar bills proposed in the past and came about after conversations with the NRA. But he insisted that the restoration program will not act as a rubber stamp for people who are not yet mentally stable and want to regain the right to own firearms.

“It’s not just a doctor’s note that’s going to get you your gun back,” he said.

Beyond that, supporters of the bill say it’s wrong to assume that mental health issues cannot be overcome.

“Mental illness isn’t something that should tar someone for life,” Brady Campaign President Paul Helmke said, adding that while the group supports the bill, it does so with some reservations.

While the Virginia Tech shootings have called attention to the problem of people deemed mentally unfit to own a weapon, Recklaus and members of the Brady Campaign said the bigger problem is that states do not necessarily put all of their felony records into the NICS; according to the bill’s findings, 21 million criminal records are not listed in the NICS.

“No one talks about those folks,” Recklaus said. “That’s where this bill’s really going to come in handy.” By giving states the financial means to include more records in the federal NICS, “It’s going to keep repeat offenders from committing guns crimes,” he said.

Helmke agreed. “This is not a perfect bill, but the good in the bill far outweighs the bad as far as we’re concerned,” he said.

As such, it’s a rare compromise that Rep. John Dingell (D-Mich.), a bill co-sponsor, said he hopes the Senate appreciates.

“[I] would caution my friends in the other body that this is a bill supported by both sides of the gun debate. That doesn’t happen much, and the legislation is balanced to reflect that agreement,” Dingell said in a statement to Roll Call.

But it doesn’t have the complete support of both sides, as Helmke’s counterparts in the gun control debate are unsettled by certain parts of the bill’s language.

The bill would require people only to prove they are not “likely” to pose a future risk and allows for an extensive appeals process for those who do not initially regain the ability to own a gun.

It also does not provide any funds to set up the restoration programs, leaving part of the gun control lobby afraid that some states may reject the NICS funding to avoid having to set one up.

“I think that states that understand the obligations and the problem with the restoration procedures that are laid out … may very well decide that it’s going to be more expensive to establish those restoration procedures than the amount of money that they would be getting from the bill,” said Sayre Weaver, a staff attorney for the Coalition to Stop Gun Violence.

Recklaus was unable to rule this out as a possibility. “I have no idea,” he said, when asked if states will have this concern.

The NRA, meanwhile, is adamant that the restoration provision remain.

“It’s vital that an individual who is healthy in all aspects and not deemed to be a threat to himself or herself or suicidal … be able to enjoy the same rights as anyone else,” said Andrew Arulanandam, the NRA’s director of public affairs.

And while opponents argue that restoration should not be tied to funding, Arulanandam said he did not see any problems. “I guess I’m having a real tough time with that question cause to me it’s germane. I fail to see where the disconnect is,” he said.

Although the bill made it through the House in June, it is still too early to determine how much support it will have in the Senate. It has been rolled into Judiciary Chairman Patrick Leahy’s (D-Vt.) School Safety and Law Enforcement Improvement Act. Lawmakers were supposed to mark up that bill last week but were unable to get a quorum.

Even if the bill does pass out of Judiciary and ultimately the Senate, some are not convinced that it will be enough to prevent another shooting similar to that at Virginia Tech.

Reporting to the NICS already is voluntary and states that participate in the program have the option of excluding from their reports the mental health records of people covered by privacy laws.

“We have no idea if [the bill] would really encourage states to submit more mental health records,” said Kristen Rand, the legislative director for the Violence Policy Center.