After each mass shooting, we see sides form. One side says "ban these guns / gun accessories" and the other side says "enforce existing laws". I am going to take a moment in this post to explain exactly what laws gun rights supporters mean when they say that.
First off are the repeat offenders. Many cities give short sentences to career criminals- people with multiple violent or gun-related offenses. Stories like this stay in people's memories for a long time. I plan to discuss this topic further in a future post if you are interested.
But how many of those are anecdotes vs whether it's an ongoing significant issue it hard to say. But a much bigger law, one which would have prevented a recent mass shooter from getting a legal gun, are more important and more easy to act on. Each state in the US is required to provide information about people who commit certain crimes (felonies and domestic abuse) as well as people declared "mentally defective" (severe mental illness) to the FBI for tracking in the National Instant Check System (NICS) database. Most states don't fully comply. This means people who should be prohibited from passing a NICS check to buy a gun can pass. In fact, this is even an issue called out by both Everytown for Gun Safety and Mayors Against Guns, two of the most prominent gun control organizations.
Even the US military has been shown to be shoddy with their compliance. This is something we can do at the state level- push our legislators to allocate resources to follow the law. As mentioned, this would have a direct impact on shooters being able to buy legal firearms.
Lastly, and most importantly, the ATF (BATFE) doesn't bother prosecuting most people who are prohibited from owning guns from lying on federal forms when they try to buy them:
"The FBI blocked 122,000 gun sales in 2002 and 2003, which represented 0.7 percent of background checks. Only 154 of the would-be gun owners—0.1 percent—were prosecuted. "
The FBI does a good job with administrating the NICS system, but even so, in 2016, 4 thousand people who are prohibited from owning firearms were able to buy one in a store and complete a NICS check.
Getting our government agencies to do a better job within the framework of existing laws is something we can do today, does not face serious obstacles, has bi-partisan support and doesn't involve getting new legislation passed. Sadly, we never focus on that, instead we battle against banning or not banning guns. It is well past time for us to focus on viable, actionable solutions instead of calling for gun bans that don't go anywhere and are ineffective at stopping mass killers anyway.