[The Louisville Metro mayor] said state legislation has tied his hands in many ways, even as his administration attempts to put long-term solutions in place to curb gun violence.
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[The mayor] was referring in part to the “Second Amendment Sanctuary” bill that made it illegal for Kentucky police officers to enforce federal firearms restrictions. The bill became law last month
Here's a report that the shooter was a star in multiple sports, but had suffered so many concussions that he wore a helmet while playing basketball in high school.