Firearm sales decreased in Colorado for the fifth year in a row, while denials of firearm transactions rose slightly, data from the Colorado Bureau of Investigation indicate.

CBI processed 342,439 background checks for gun purchases in 2019, the lowest since 2014. The majority of sales were for handguns, and in December the average time to perform the check was 10 minutes and 29 seconds. Just over 2% of those checks resulted in a denial of transaction.

The CBI’s InstaCheck unit performs background investigations for every firearm purchase. The background checks are a proxy for firearm transactions, although there is not a tracking mechanism for every type of gun transfer.

The top reason for denial of sale was that a background check turned up an arrest or conviction for assault. Over 1,000 transactions in 2019 were also halted due to drug crimes. The presence of restraining orders, burglary, larceny and sexual assault crimes each blocked between 109 and 454 purchases.

The Federal Bureau of Investigation reports that since the federal criminal background check system started in 1998, there have been 1.7 million denials nationwide, more than half of which were due to a prior conviction for a crime.

Background checks in Colorado for calendar year 2019 represented a 235% increase in the number of checks performed in 2001. Of the approximately 2,144 people who appealed their denial in 2001, half of those appeals were reversed. In 2018, the ratio was roughly the same: 53% of the 3,536 appeals resulted in a reversal.

A CBI spokesperson said that the burden in appeals is on the bureau to prove its case based on a person’s criminal history, and not on the individual who received the denial.