Butte, Montana (CNN) -- Five years ago, Leo McCarthy lost his 14-year-old daughter, Mariah, when a drunken driver hit her and two of her friends as they walked down a sidewalk near her home. But he refused to let her tragic death become just another statistic. Knowing that the driver was 20 years old -- not even old enough to drink legally -- McCarthy made an unusual promise to the teenagers attending Mariah's memorial service in Butte, Montana. "If you stick with me for four years," he said during her eulogy, "don't use alcohol, don't use illicit drugs but give back to your community, work with your parents and talk to your parents, I'll be there with a bunch of other people to give you money."
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Leo McCarthy is challenging Montana teens to stay away from alcohol
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His daughter, Mariah, was killed in 2007 by a drunken driver who was underage
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More than 140 teens have taken Mariah's Challenge and gotten scholarships
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Those troublesome statistics, along with @placeholder's story and other high-profile deaths, have led legislators to seek more aggressive ways to address the issue.