A judge blocked Boulder’s ban on assault-style weapons but it hasn’t gone to the state Supreme Court

Ten people died in a mass shooting at a King Soopers supermarket in Boulder, Colo., on March 22. Police have arrested and charged a 21-year-old who with 10 counts of murder. 

Even as more information about the incident became known, rumors and misinformation rapidly spread online. 

A screenshot of a tweet shared on social media soon after the shooting suggested that the incident was related to the city’s ban on assault-style weapons. But it gets some history wrong.

"Last week, the Colorado Supreme Court declared that Boulder’s AR-15 ban was unconstitutional. Today, there was a mass shooting in Boulder," the tweet says. "The timing of this is very coincidental, to say the least."

This post was flagged as part of Facebook’s efforts to combat false news and misinformation on its News Feed. (Read more about our partnership with Facebook.)

In 2018, the city of Boulder enacted a ban on the possession, transfer or sale of assault-style weapons and large-capacity magazines.

On March 12, more than a week before the shooting, Boulder County District Court Judge Andrew Hartman ruled that the city can’t enforce the ban due to a 2003 state law that says local governments can’t prohibit the possession or sale of firearms, the Post reported.

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The city has not announced if it will appeal Hartman’s ruling, and the case has yet to reach the Colorado Supreme Court. If it does, "justices there could for the first time issue a statewide ruling on whether local governments can pass more restrictive gun laws," the Post said. 

In 2006, the state Supreme Court allowed an assault weapons ban in Denver to stand in part because the city’s ban predated the state law by more than a decade, according to the New York Times. But that ruling did not set a binding precedent for future cases because the court was divided 3-3 on whether Denver’s ban was legal. That left in place the lower court’s ruling in the case.

Police have not yet identified the exact weapon used in the supermarket shooting but the New York Times reported on March 23 that "a federal law enforcement official confirmed that the weapon used was some version of an AR-15 rifle." A police affidavit said the suspect had both a rifle and pistol at the store and that an officer "observed the suspect with an assault rifle of unknown make and brand who was shooting toward him." It also noted that the suspect purchased a Ruger AR556 pistol on March 16. 

Our ruling

The post says that a week before a mass shooting in Boulder, the Colorado Supreme Court declared that Boulder’s AR-15 ban was unconstitutional.

The post is partially accurate but got some important details wrong. A little more than a week ago, a district court judge ruled that the city’s ban on assault-style weapons wasn’t legal under a 2003 state law, not the U.S. or Colorado constitution. 

The Colorado Supreme Court has yet to consider the case, and the city hasn’t announced if it will appeal the decision. 

We rate this claim Half True.