The idea came to him, appropriately enough, on Mother's Day. Jim Harris was tired of standing by while his ailing mother, who was convicted of murder in 1981, lived out her final years in a maximum-security prison. So he decided to do what he believes any loyal son would do—take to the streets to gather support for a clemency plea.

If Harris were just any loyal son, his crusade might go unnoticed. But he is the offspring of Jean Harris, the former private school headmistress who received a 15-years-to-life sentence for killing her former lover, Scarsdale Diet Doctor Herman Tarnower. In an emotional, much publicized trial, Harris pleaded innocent to the murder charge, claiming she had been in despair over the doctor's waning affections. She had shot him by accident, she said, when he interfered with her suicide attempt. The jury was unconvinced, and Harris was sent to the Bedford Hills Correctional Facility in Westchester County, N.Y., with no possibility for parole until 1996. Five years later and with her appeals exhausted, Harris is 63 and in increasingly poor health, suffering from a heart condition.

After two days stationed near New York's Grand Central Terminal, Jim had 3,200 signatures on his petition urging New York's Gov. Mario Cuomo to grant Harris an early release. "It's been hard seeing Mother being broken down in prison," he says. "She keeps busy working at the [prison's] children's center, teaching classes and knitting sweaters for friends. But you only can keep yourself up for so long." His efforts are supported by his brother David, 36, and not surprisingly by his mother, who first heard of her son's actions on a TV news show. "I didn't tell her about it beforehand because I didn't want her to worry," explains Jim. "But I knew she'd like it."

Neither the petition nor its author addresses the question of Jean Harris' guilt or innocence; both state simply that her release would not harm society and that continued incarceration is a threat to her health. There has been no comment so far from Cuomo. But the 33-year-old bachelor, who left his job as a bond trader a few weeks ago, is ready to continue his fight for as long as it takes. "The governor hasn't said, 'Jim, if you get 7,416 signatures, it's a go; you're a winner,' " he says. "So I'm just getting as many as I can. I'm going to be out here for a while."