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The issue of abortion has divided Americans for decades, but questions about science and justice have blurred the lines for a woman who finds herself fighting for an issue that would seem to contradict her personal views.

Tracy Marciniak supports abortion rights, but has become a champion of pro-life groups since losing her unborn son Zachariah five days from her due date. Marciniak lost the baby when her then-husband Glendale Black punched her in the stomach.

Black got 12 years for attacking Marciniak, but under Wisconsin law at the time he could not have been charged with murder.

"His father got away with murder! He got away with murdering his own son," Marciniak said. "Here, I not only lose my son, but now the state is telling me that my son didn't exist."

Angry over the lack of legal recognition of her son, the pro-choice Marciniak worked six years on a pro-life cause — legal protection for the unborn.

On the state level, she succeeded when then-Gov. Tommy Thompson (search) signed into law a measure in 1998 that said that from conception through birth, killing the unborn in Wisconsin is murder. The only legal exception is abortion.

Although pro-choice groups have insisted the law could be used someday to make abortion illegal, Marciniak disagreed.

"It's been in effect for five years in Wisconsin and hasn't changed a woman's right to have an abortion," she said.

Recently, Marciniak was on Capitol Hill advocating a bill sponsored by Rep. Melissa Hart, R-Pa., called the Unborn Victims of Violence Act (search).

The legislation would make it a federal crime to cause the death of a developing child at any stage of pregnancy. The bill's language specifically exempts abortion, but its pro-choice opponents charge that if the bill became law, a woman's right to choose would be in jeopardy.

"It defines in the law eight cells as a human child with rights, and that's not what the Supreme Court has said," said Rep. Zoe Lofgren, D-Calif.

Planned Parenthood (search) has said that if the Unborn Victims of Violence Act were made into law, it would bestow "personhood" on a fetus because the law would create a separate charge and separate penalty for killing a fetus.

Organization officials say if the legislation were passed, it would be on a collision course with Roe v. Wade, the 1973 Supreme Court ruling that made abortion legal.

"It is about making the fetus have all the rights in law and taking rights away from the woman," said Gloria Feldt, president of Planned Parenthood of America.

Despite the opposition, Hart said she believes it will pass the House.

"The question has always been what will happen to it in the Senate," Hart said.

That remains the question, particularly in light of the publicity paid to the murder of California woman Laci Peterson and her unborn son Connor.

"The Laci and Connor situation, as tragic as it is, is actually going to serve a purpose here," said Sue Armacost of the Right to Life Committee (search).

In line with California's fetal protection law, Laci's husband, Scott, has been charged as the main suspect in two murders — Laci's and Connor's.

By year's end, 28 states will have laws on the books that protect the unborn. In 15 of those states, legal protection begins at conception.

Laci's mother, Sharon Roche, said she would like to see the law expanded to a federal act.

"Connor was a person. There wasn't one murder. There were two murders here," Roche told Court TV.

Fox News' Steve Brown contributed to this report.