By Terry Baynes

(Reuters) - When a federal judge on Wednesday struck down an Idaho law that banned most abortions after 20 weeks of pregnancy, lawyer Richard Hearn scored a double victory.

In an unusual maneuver, Hearn, who is also a physician, had intervened in the case as a plaintiff in June. Hearn made the move after the court found that his client, a woman accused of illegally taking abortion-inducing drugs, lacked standing to challenge the law since it only penalized doctors who perform late-term abortions.

U.S. District Judge B. Lynn Winmill on Wednesday found that even though Hearn had never performed an abortion, his stated intention to prescribe abortion-inducing drugs in the future gave him grounds to challenge the law.

"The injury requirement is satisfied by both a credible threat of prosecution and a potential chilling effect on Hearn's medical practice," Winmill wrote.

As a result, Hearn could assert the rights of women seeking an abortion, Winmill found. The ban, he wrote, violated a woman's constitutional right to an abortion up until the point a fetus can survive outside the womb, around 22 to 24 weeks into the pregnancy, under U.S. Supreme Court rulings.

"I am very pleased, and that may be an understatement," said Hearn.

Idaho is one of at least eight states to pass a late-term abortion ban based on controversial medical research suggesting that a fetus starts to feel pain at 20 weeks. Winmill was the first judge to strike down a fetal pain ban on its merits, Hearn said.

Hearn stopped practicing medicine regularly in 1997, becoming a full-time attorney. His practice primarily included civil rights, criminal and personal injury cases when Jennie McCormack retained him for legal help.

McCormack, an unmarried mother of three, had been charged by Bannock County prosecutors under a 1972 Idaho law that requires abortions be performed by a provider at a licensed facility. She had terminated her pregnancy at around 20 weeks with an abortion-inducing drug obtained on the Internet. Prosecutors eventually dropped the charges, but McCormack sued to challenge several state abortion laws, including the 20-week fetal pain ban adopted in 2011.

Unable to find any doctors in Idaho willing to perform abortions as late as 20 weeks to serve as plaintiffs in the case, Hearn decided that his only option to keep the challenge to the fetal pain law alive was to step into the suit himself.

READING ABOUT RU-486

He initially was concerned about the potential ethical conflicts of serving as both plaintiff and lawyer in the same case, but after consulting with the Idaho Bar and other lawyers he felt that it was appropriate.

"Because I was intervening for Ms. McCormack's rights, and not for myself, for example to win money, I was given the green light," Hearn said. "It would have been much more complicated if I was trying to win something for me," he added.

Hearn said he saw his intervention in the case as a technicality needed for McCormack to vindicate her constitutional rights to a late-term abortion. He lamented the fact that a doctor, especially a male doctor, had to intervene on her behalf.

Hearn hired his own lawyer as a precaution in case his interests ever diverged from McCormack's, he said. But his lawyer, Jack Van Valkenburgh, did not play an active role. Hearn argued the case on McCormack's and his own behalf before the court in December.

As a full-time doctor, Hearn specialized in nephrology, or kidney diseases, and rheumatology, or autoimmune diseases involving joints and tissue. Since taking on McCormack's case, he has read more about RU-486, the abortion-inducing drug, than he ever would have in medical school, he said.

In order to have standing to challenge the fetal pain law, he had to say that he would prescribe abortion-inducing drugs if the Idaho laws were not in place.

"The law only requires that I express a genuine intent to prescribe these medicines, which I did and do have," he said. The state did not challenge the sincerity of his intent, Hearn said.

The state attorney general argued that Hearn could not have standing simply by saying that he had an intention to perform medical abortions in the future. He would also need to have a properly equipped and staffed medical office with arrangements for emergency care, or privileges at a hospital to claim the right to perform abortions, the state argued.

But Winmill disagreed, finding that Hearn, as a legally licensed physician, could prescribe medication to induce abortions outside clinical settings, and that Idaho's fetal pain law infringed on his right to practice his medical career.

"I never imagined returning to a medical role through a lawsuit. Neither did my wife or children," Hearn said.

He said he hoped that the court's latest ruling would encourage other physicians to readily prescribe drugs for late-term abortions now that it's legal. But if no other doctor did, he would have to prescribe them himself.

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