The Supreme Court will weigh a Trump-era ban on bump stocks for guns. Here's what to know.

Washington — The Route 91 Harvest Music Festival in Las Vegas was becoming an annual tradition for Geena Marano Springmann. She had attended the three-day country music event with her best friend in 2016, and they returned the next year with Springmann's oldest sister.

But that year, as singer Jason Aldean was performing around 10 p.m., Springmann recalled hearing what first sounded like fireworks, but soon realized were gunshots, raining down from a window on the 32nd floor of a hotel and casino across the street. After being shielded by her sister, Marisa Marano, for several minutes, the women ran to a casino on the Las Vegas Strip. Springmann texted her mother to tell her that there was a shooting at the concert, they were running and she loved her.

Fifty-eight people were killed in the rampage — two others died later — and roughly 500 were wounded. The October 2017 massacre is the deadliest mass shooting in modern U.S. history, and it served as the catalyst for federal action that is now under review by the Supreme Court.