Logging his first arrest at age 22, in 1945, Harrison drew a term of five to ten years on conviction for a Chicago armed robbery. While locked up at Menard, he struck and killed another inmate -- convicted murderer Norman Kimme -- in November 1951, earning a stint in the state hospital after he was deemed incompetent for trial. Upon parole, there would be more convictions, eight in all, on various charges including larceny, attempted armed robbery, unlawful use of a weapon, battery, and indecent exposure. Harrison jumped bail twice, and twice more was sent back to state hospitals for diagnosis and treatment. Found competent for trial on robbery charges in March 1972, Harrison was convicted and sentenced to eighteen months, then released by a judge on the basis of time served during psychiatric evaluations. Through it all, no one suspected Harrison of possible involvement in a string of grisly homicides committed around Grant Park, in downtown Chicago.

Agnes Lehman was the first victim , beaten to death near the park's bandshell on July 10, 1970, her body found the next morning. A shoe recovered at the scene was linked to suspect Wilbur McDonald, arrested twelve days later as he lay unconscious by some railroad tracks, the victim of a mugging. McDonald admitted speaking with Lehman the night of her death, but insisted a black man had rushed from the darkness, assaulting them both and putting McDonald to flight. Skeptical jurors rejected the story, convicting McDonald of murder, and the court handed down a sentence of 100 to 150 years in prison.

Authorities saw no reason to reopen the case on September 5, 1972, when Judith Betteley was beaten to death a few yards from the old murder scene. Three weeks later, Lester Harrison was charged with assaulting 31-year-old Cozetta Gladys, knocking her down with a brick and dragging her through a Chicago alley. Released on $5,000 bond September 28, he was subsequently found competent for trial, and formally indicted on December 29. A judge allowed the meager bail to stand despite his violent record and long history of mental disorders.

Harrison's trial was still pending in July 1973, when Irene Koutros was stabbed to death in Grant Park's underground garage. Three weeks later, on August 3, Lee Wilson was fatally stabbed in the park proper, her assailant pausing to gnaw on the body before he escaped. On August 13, 28-year-old Judith Ott was knifed to death in a park restroom, a black man observed sprinting from the scene of the attack. The victim's husband, David Ott, gave chase and tackled Harrison, unaware that his wife had been murdered nearby.

In custody, Harrison confessed to four of the Grant Park murders, staunchly denying a role in the case of Irene Koutros. Aroused by the thought of female suffering, Harrison derived satisfaction from beating and stabbing his victims, once sampling cannibalism in the case of Lee Wilson. In addition to his confessed crimes, police sought links in the death of 28-year-old Elizabeth Dawson, recovered in August 1972 from a derelict building next door to Harrison's home.

Defense motions and psychiatric examinations delayed Harrison's murder trial until 1978, when he was acquitted on grounds of insanity . Unwilling to set the diagnosed schizophrenic "lust killer" free, prosecutors convened a special hearing to have Harrison declared "sexually dangerous," dusting off a little-used state law to have him confined while he remained a menace to society.

By May 1986, a 62-year-old quadriplegic, Harrison found attorneys to seek his release from state custody. Lawyers described Harrison as "harmless," asserting that he could "hardly" move in his present condition. The state countered with testimony from guards at Belleville State Hospital, suggesting that Harrison was capable of raising his arms, that he spoke incessantly of sexual activity, and that he was visibly aroused when certain nurses entered his room. As Terry Levin, spokesman for the state attorney's office, told the court, "If Lester Harrison were able to get his hands on any woman that woman would be in danger of being killed. If he could use one leg, he would try to use it to kick somebody to death. If he could use one arm, he would use it to try to beat somebody to death." The petition seeking Harrison's release was withdrawn on August 11, 1986.