A mother's mission to find her daughter's killer

A heartbroken mother's mission of love has brought her from Oklahoma to Houston.

Dr. Maggie Zingman’s daughter was brutally murdered 13 years ago, and that pain is what drives her today.

Her goal is to educate people about sexual predators and she's doing it by crossing state lines.

“When I first got that news, like any parent, I thought I was going to die,” said Dr. Zingman.

Dr. Maggie Zingman, a trauma psychologist, got the news at 1 a.m., 13 years ago in Oklahoma. Her daughter had been murdered.

“She lay there three days in her second story apartment, dead, after she had been raped and suffocated and the only thing that doesn’t torture me is that from [what] the M.E. told me, she died instantly,” said Dr. Zingman.”

The killer, to this day, is still free, living among us in society.

Now, each year, she travels all over the country, driving a pink and purple caravan to look for tips and to encourage a change in the role of DNA testing in crime laws.

“When you find out, it opens this hole inside of you, and you think there’s no way to survive, but these caravans have actually been life-giving for me,” said Dr. Zingman.

She has driven 163,000 miles over the years, meeting new people every day to talk to other grieving parents.

“Even though I still look for tips, it’s more about the laws and really telling parents you don’t have to die when your children are taken from you,” said Dr. Zingman.

Her ultimate goal is to spread her message about the importance of DNA testing for suspects.

“We went through everybody she knew -- male friends, friends of friends, and none of the DNA matched, and then we started looking at different suspects, and by year two, we had over a thousand suspects in Oklahoma whose DNA did not match the killer’s,” said Dr. Zingman.

Dr. Zingman's hope is that our laws in Texas will change. Statistically, sexual predators often commit other types of crimes, like assault, and she believes if DNA were collected during arrests, even on misdemeanor crimes, that this broader net in the DNA database would bring more criminals to justice.

To visit her website, go to: http://www.brittanyphillipsmurder.net/