BOISE, Idaho (AP) — A poor woman in rural Idaho was looking for help after authorities said they found an aborted fetus in a box on her back porch.

Jennie Linn McCormack had been charged with giving herself an illegal abortion using drugs purchased online, and she faced five years in prison if convicted.

She had three kids, little money and less hope when she walked into a lawyer's office in Pocatello and told her story to Rick Hearn, who has a soft spot for underdogs.

"Her circumstances pulled on my conscience," he said.

"I wanted to represent Jennie."

He had no idea his decision would turn into the nation's first lawsuit challenging the so-called fetal pain laws enacted in more than half a dozen states. Nor did he suspect he would end up trying to intervene in the lawsuit on behalf of a doctor who had never been involved with terminating a pregnancy — himself.

Hearn, who had already finished medical school when he decided to get a law degree, is using a legal strategy that many experts say is unheard of.

"This is like nothing that I've ever read about or encountered," said Bill Horton, a legal ethics expert associated with the American Health Lawyers Association and the American Bar Association's health division. "But these abortion rights lawsuits tend to bring out unusual strategies sometimes."

Hearn is trying to join the case as a plaintiff in an effort to overturn Idaho's fetal pain law as unconstitutional. The strategy is so novel that legal observers can't predict how it will turn out.

The doctor-lawyer says he is simply doing the right thing for his client.

"I was forced to take this highly unusual step," he said. "I didn't want to."

He says he frequently works with people who can use all the help they can get.

"I normally represent the small people who are suing government or corporations," he said. "And I do some criminal defense."

McCormack came to him early last year, saying that she was a single mother living on between $200 and $250 a month and faced felony charges.

Authorities say on the day before Christmas in 2010, McCormack took abortion drugs to terminate a pregnancy that was more than five months along. An acquaintance heard that she'd done it and called police, who looked into the claim said they found a fetus in a box on her porch.

The county prosecutor charged McCormack under an Idaho law that makes it illegal for anyone other than a health care professional to be involved with terminating a pregnancy. Hearn defended McCormack and the case was dismissed. But it wasn't a total victory, a judge tossed the charges "without prejudice," meaning she could be prosecuted again at any time.

Meanwhile, Idaho lawmakers passed the fetal pain law.

Such regulations ban abortions after 19 weeks of pregnancy, under the premise that a fetus may feel pain at 20 weeks.

The scientific research that bolsters the measures has been the subject of heavy debate, but such bans have been gaining momentum among conservative legislators. A plan passed last year in Idaho with overwhelming support.

Hearn didn't want McCormack living with the constant threat of prosecution and decided to turn the tables. Rather than wait for the law to come after his client, he and McCormack decided to go after the law.

They sued in federal court last September, fighting for McCormack's right to take medication to induce an abortion and for doctors' rights to prescribe such drugs. They also took aim at the fetal pain abortion ban, which they felt also violated women's constitutional rights to privacy.

But U.S. Judge B. Lynn Winmill ruled the lawsuit wouldn't get class-action status and that McCormack didn't have the right to challenge some aspects of the law because she wasn't currently pregnant and seeking an abortion.

So Hearn went one step further, filing a motion to intervene as a plaintiff himself, in his role as a physician who may want to prescribe abortion-inducing drugs in the future.

Never mind that Hearn hasn't practiced medicine for about six years — his license to practice is still current, he said.

And never mind that he's never performed an abortion, nor does he intend to. In fact, he's Catholic, and the church is strictly anti-abortion.

But Hearn says he's reconciled his personal beliefs with his professional efforts to help McCormack in her legal fight.

"Neither I nor my family are seeking abortions, and we would not. But Jennie is not Catholic," Hearn said. "This is about her right to choose."

Deputy Idaho Attorney General Clay Smith dismissed Hearn's move as merely an attempt to introduce issues that McCormack has no standing to present.

Hearn doesn't dispute that.

"I'm not trying to trick anybody or anything," he said.

He added, "I'm intervening in order to assert her right to obtain an abortion, and the courts have said that doctors can assert the rights of their patients."