The man accused of shooting and killing 10 people at a grocery store in Boulder on Monday had legally purchased a Ruger AR-556 rifle six days earlier.

Alleged gunman Ahmad Al Aliwi Alissa, 21, of Arvada, was found guilty of third-degree assault as a high school senior in 2018 after punching and kicking a fellow student in a classroom after being called “racial names,” according to a police affidavit.

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Alissa’s 2018 assault charge was a misdemeanor.

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But most misdemeanors don’t stop you from getting a firearm, said Paul Paradis, owner of Paradise Sales gun shop west of downtown Colorado Springs.

“For society, it is a warning sign that maybe we’ve got to sit down with this kid and figure out what is going on to see if we have a problem.”

Anyone wanting to purchase a gun in Colorado is required to fill out a firearms transaction record. The information is submitted to the Colorado Bureau of Investigation, where a local background check is done. A national background check is done through the Federal Bureau of Investigation.

On an average day, Paradis said there are 100 to 150 people awaiting a background check, but that the number can vary widely throughout a given day.

“In good times it could take 15 to 30 minutes for it to go through,” Paradis said Wednesday. “Right now there are about 2,200 people waiting, so it is taking two to three days for a background check to be done.”

Once an individual’s background check has been approved, they can return to the store and sign for their gun.

Pradis has processed more than 30,000 background checks and said that roughly one in 50 comes back denied. Customers can appeal the denial, and Paradis sees about one in six appeals overturned.

Some of the reasons for a denial include a felony conviction, a dishonorable discharge from the military, a domestic violence misdemeanor or drug use, including those with a medical marijuana card who smoke pot.

Last year, the Colorado Bureau of Investigation performed more than 500,000 background checks for gun sales, the most in state history, according to the CBI.

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