Susan Endersbe, a schizophrenic who lived in Minneapolis, battled depression all her life. When her illness worsened, she usually checked into a hospital, which she did for the last time on May 7, 1994. On that occasion, doctors gave her an antidepressant, and three weeks later she said she felt ready to leave soon, according to nurses’ notes.

The next day, she was referred to Dr. Faruk Abuzzahab and agreed to participate in a drug study he was being paid to conduct, although her suicidal tendencies should have excluded her. Dr. Abuzzahab stopped giving her the antidepressant, and she was forced to wait nearly two weeks before receiving either an experimental drug or a placebo.

Throughout those weeks, Dr. Abuzzahab recorded Ms. Endersbe’s adverse effects as “0,” but nurses documented a steady decline. Ms. Endersbe expressed reservations about being part of a study. “I guess I didn’t understand that I would be going off all my other medications,” she told a hospital worker, according to records.

She spoke repeatedly of killing herself, even telling a nurse in a late-night talk on June 8 that she planned to jump off the Franklin Avenue Bridge, “but says she is safe in the hospital,” a hospital worker wrote.

On June 10, Dr. Abuzzahab wrote in her chart that Ms. Endersbe was “medically improving.” He gave her permission to visit her apartment alone, although leaving the hospital violated the study’s rules and she had spoken of suicide only the night before.

Saying she wanted “to water my plants and pick up my mail,” Ms. Endersbe, 40, left at 10:45 the next morning. She walked the five blocks to her apartment, retrieved a St. Francis of Assisi medallion given by her mother, locked up, slid her keys under the door and walked to the Franklin Avenue Bridge where, at noon, she jumped to her death.

Dr. Abuzzahab would not comment on particular cases but said the state medical board’s disciplinary action against him was “without heft.”

Ed Endersbe, Susan’s brother, said the authorities called him about his sister’s death at his daughter’s birthday party.

“My mother was battling cancer and I had to go and tell her that Susan was gone,” Mr. Endersbe said. “I literally watched my mother’s heart break, and she died three months and a day after that.”

Mr. Endersbe said he was stunned to learn years later from The New York Times that Dr. Abuzzahab was still overseeing clinical trials.

“He should not be allowed to harm anyone else,” he said.