Formed in the aftermath of the horrific 2012 mass shooting at Sandy Hook Elementary School, Moms Demand Action for Gun Sense in America is now a vital national voice in the movement to end gun violence.

The Minnesota chapter of Moms Demand Action, and its volunteer chapter director Marit Brock, led an effort this spring to pass legislation requiring criminal background checks on all gun sales in the state. Despite polls that showed broad statewide support on the issue, a bill on the matter stalled in committee and failed to get a floor vote. Still, Brock remains undaunted. "I believe that our common sense, evidence-based approach, tied with a real grassroots movement," will lead to legislative success.

The group has momentum. In 18 months its active volunteers have grown from about 100 to more than 1,600, with a statewide membership numbering over 70,000. "As we spread the word about how to get involved with Moms Demand Action in Minnesota, we hear from moms, dads and grandparents horrified that we have created a world where children have to endure lockdown drills as part of school and preschool life," Brock says. "This isn't pro- or anti-gun politics. This is a public health and safety issue."

After all, she adds, "in the 18 states where [expanded background checks are] now law, they have seen gun deaths cut in half across the board, including suicide, homicide, and domestic violence deaths."

Brock knows firsthand that gun violence is more than horrific single events that make worldwide news. Her brother took his life with a gun in 2001. "I quickly realized that easy access to guns and gun suicide go hand in hand," she says. Many Moms Demand Action activists are compelled by similar tragedies. "We are working to make sure no other family has to go through what we have gone through," Brock says.

Moms Demand Action works to create what Brock calls "a culture of responsible gun ownership" with respect for the Second Amendment. Its #NotAnAccident index tracks incidents of children under 17 who are killed or injured unintentionally by firearms, and its BeSMART campaign offers resources for families to keep children safe.

Though its members aren't necessarily women or even parents - Brock says they call themselves "mothers and others" - she believes it is important that the group's name reflects its grassroots origins as one mother's response to Sandy Hook. Shannon Watts, an Indiana mother of five, started a Facebook page called One Million Moms for Gun Control the day after the shooting; the page proved so popular that it made the leap from social media to the advocacy of Moms Demand Action.

Brock's youngest child was in first grade in 2012, the same age as many of the children who died. "There is no one more qualified to fight fearlessly for the safety and future of children than a mother," she says, "whether it is safety on play dates, keeping guns out of the hands of children, or protecting our children from domestic violence or suicide."

Learn more about how you can get involved in ending gun violence: