From USA Today:

Colorado gun laws that mandate background checks on private sales and that limit ammunition magazines to 15 rounds are constitutional, a federal judge ruled Thursday.

[ . . . ]

In her 50-page ruling, U.S. District Judge Marcia Krieger wrote “evidence shows that large-capacity magazines are frequently used in gun violence and mass shootings, and that often a shooter will shoot continuously until a weapon jams or the shooter runs out of ammunition.”

“Most experts agree that the size of a magazine correlates to the number of rounds that are fired in both an offensive and defensive capacity,” she added.

But the plaintiffs — gun owners, advocates, manufacturers and sheriffs — had presented no evidence that someone’s ability “to defend him or herself is seriously diminished if magazines are limited,” Krieger declared.

More from the judge’s decision at the link.