Initially, Ms. Burkhart said, “He scared the crap out of me,” with his defiance in the face of death threats and a dry sense of humor that people sometimes mistook for brusqueness. But they were “simpatico,” she said. She didn’t mind that he called her at 1 in the morning, since she was up working too.

“He really understood, and I understood, that this work is risky, you have to take risks, you have to think outside the box and sometimes you have to make big, difficult, challenging decisions.”

Over the next eight years she became the public face of his clinic in state politics. She appreciated his approach to the Legislature, that he resisted efforts to enact even seemingly innocuous regulations on abortion providers — requiring that their procedure rooms be larger than those in other surgical practices, for example — because he believed those laws would only make it easier for abortion opponents to push for more restrictions.

Dr. Tiller’s opponents accused him of running a “baby killing factory,” but Ms. Burkhart saw only deep commitment. “To his practice, and to people,” Ms. Burkhart said. “I really admired that, that he felt that everybody deserves forgiveness, redemption, that it’s part of life.”

In May 2009, an extremist who later testified that he had planned for many years to kill Dr. Tiller fatally shot him at his church. The funeral was standing room only. Ms. Burkhart recalls mostly her rage. The political action committee Dr. Tiller had started, ProKanDo, had been the state’s biggest donor to campaigns, yet she felt that the politicians it supported had been too timid to speak up for him, or abortion rights. “I remember people saying, ‘This is devastating, this is horrible, how can this happen?’” she said. “I was like, ‘How the hell do you think this happened?’”