Thanks to a disagreement between the FBI and the Bureau of Alcohol Tobacco Firearms and Explosives (ATF), more than 2,000 guns were purchased in the past 15 years by people the FBI said should not have had them, according to a new report from the Office of Inspector General.

In an election year, when the two candidates have taken dramatically different stances on the issue of gun control, the topic has come to the center stage. Led by the efforts of President Obama, whose administration has weathered some of the worst mass shootings in the nation’s history, Democrats have called for stricter gun control laws, including some that would increase background checks and place bans on where gun owners can carry the weapons. Republicans in Congress have sought to block such measures, and Republican presidential candidate Donald Trump, who is backed by the National Rifle Association (NRA), has run on a platform promising to protect the rights of gun owners, arguing that the current laws are strict enough.

But this new report, which uncovered a loophole through which some of those deemed unfit to own firearms by the FBI can purchase them, puts a new scrutiny on the current laws, and how they're enforced.

The FBI is responsible for running background checks on those purchasing guns. If the agency finds those buyers unfit, the responsibility to retrieve them falls on the ATF.

But the two federal agencies disagree on who qualifies as a “fugitive from justice,” a label that prohibits prospective buyers from acquiring firearms, USA Today reports. While the FBI has considered anyone with an outstanding warrant to fall under the category, the ATF argues that prospective gun owners should be allowed to purchase firearms in the state where they have a warrant, but not in other states.

The FBI sought to clarify the discrepancy by bringing the issue before the Justice Department’s Office of Legal Counsel. There, the agencies received “informal advice.” When the FBI requested a more formal ruling two years later, the counsel failed to render a decision, allowing the issue to persist some six years later.

The focus of prosecutors has also shifted in recent years when it comes to enforcing gun laws, according to CNN. Following the 2012 shooting at Sandy Hook Elementary, Mr. Obama told prosecutors to make cases involving illegal trafficking and violent offenders a priority. The result was a drop in cases involving buyers later determined ineligible: Of 558 cases the ATF brought to prosecutors, only 254 were accepted.

The report called for clarification on the “fugitive of justice” discrepancy to ensure proper enforcement of the law.

"We recommend that the OLC issue an opinion as soon as possible to clarify the correct definition of the 'fugitive from justice' category of the persons prohibited from purchasing a firearm,'' the review concluded. "Only then can ATF and the FBI be certain the law is being applied appropriately and as intended.''