Columbine 25 years later: US lawmakers struggle to reduce gun violence decades after tragedy

Twenty-five years after two senior students entered Colorado’s Columbine high school and opened fire, killing a teacher and 12 students, there are still so many lessons to take away from that tragedy. Since Columbine, there have been more than 400 school shootings across the U.S. As Caryn Lieberman reports, U.S. lawmakers have struggled to roll out tougher firearms legislation and reduce gun violence.

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