AUSTIN (KXAN) — After the Sutherland Springs church shooting, Congress passed the Fix NICS Act into law, spurred on by Texas Senator John Cornyn.

The act was introduced by Cornyn after it was discovered that the shooter should have been denied the purchase of a rifle because of a 2012 domestic assault conviction.

The man was still able to purchase a rifle, however, and killed more than 20 people in the small Texas town.

According to reports, the U.S. Air Force failed to enter the conviction into the national background check system —the National Instant Criminal Background Check System — making the purchase possible.

In a letter Cornyn’s office sent to the U.S. Attorney General, there has been a 400% increase in background check submissions since the act was passed into law.

MORE: Sutherland Springs church unveils new sanctuary after shooting

But the Department of Defense and the Department of Homeland Security have not yet complied fully.

“These missing records undermined the effectiveness of the NICS system and put innocent lives at risk,” said Cornyn and Connecticut Democratic Senator Chris Murphy, in the letter.

Austin security expert, Jeff Broaddus, with Broaddus Defense, says departments with thousands of people might take a little longer than police departments.

“The backlog of criminal conviction records that maybe haven’t been reviewed, probably going to take a little more time I would think than a year,” said Broaddus.

“The important thing about Fix NICS might not necessarily be that it prevents these instances but it does represent an effort by lawmakers to hold agencies that have the responsibility to report accountable by providing civil and criminal penalties for not reporting and incentivizing proper reporting with grant funding incentives,” said Broaddus.

“It by no means prevents someone from either obtaining a firearm illegally or using a lawfully obtained firearm to perpetrate violence,” said Broaddus, but says the Fix NICS Act does show improvements can be made on a bipartisan basis, despite the political rhetoric surrounding guns.

The act does not impact private sales: person-to-person gun sales that do not require background checks, such as a purchase between family members or gun shows.

According to the Fix NICS Act, all agencies must submit new convictions to the FBI’s NICS system twice a year, with the latest being July 31.

The Fix NICS Act requires all federal agencies and states to upload data to the NICS system. If not, the federal agencies will be publicly reported and ban bonus pay. States that comply will get preference in applying for federal grants or incentives. The head of each federal agency or department must certify with the U.S. Attorney General whether they are compliant twice a year.

Part of the law created a Domestic Abuse and Violence Prevention Initiative, which helps states upload information on felons or domestic abusers unable to purchase weapons.

KXAN reached out to both the Defense and Homeland Security departments to ask about their enforcement of the Act but hasn’t heard back yet.