Jaclyn Marie Dowaliby was a seven-year-old girl who lived with her family in Midlothian, a suburb south of Chicago in Cook County, Illinois. On the morning of September 10, 1988, she was discovered missing from the home. Her family reported that she appeared to have been taken during the night, and investigators examined a basement window that was treated as a possible point of entry. Four days later, on September 14, 1988, her body was found on open ground near an apartment complex in nearby Blue Island. An autopsy attributed her death to strangulation; a length of cord was found knotted around her neck.
On November 22, 1988, Jaclyn's mother, Cynthia Dowaliby, and her adoptive father, David Dowaliby, were arrested and charged in connection with the death, and a grand jury indictment followed. Their joint trial opened on April 5, 1990, in Cook County Circuit Court before Judge Richard E. Neville. In May 1990, the judge directed a not-guilty verdict for Cynthia Dowaliby, ruling that the evidence against her was legally insufficient. On May 3, 1990, a jury convicted David Dowaliby, and he was sentenced to a total of 45 years in prison — 40 years for murder and a consecutive 5 years for concealing a homicide.
On October 30, 1991, the Illinois Appellate Court unanimously reversed David Dowaliby's conviction, finding that the evidence was legally insufficient and that the testimony central to the prosecution was not persuasive. The court ordered his release without a retrial, and he was freed in November 1991 after spending 583 days in custody. On February 5, 1992, the Illinois Supreme Court declined to review the matter, ending the prosecution. Because of constitutional protections against double jeopardy, neither parent could be tried again for the killing.
No one else has been charged in Jaclyn Dowaliby's death. Prosecutors briefly revisited the case in January 1993, but no new charges resulted, and later reporting described it as a cold case with no fresh leads. The killing remains officially unsolved and has been described as one of the Chicago area's most prominent unresolved child-homicide cases. It has been examined in a 1992 Unsolved Mysteries broadcast, a 1994 book by two journalists, and a 1996 made-for-television film.