About 1 a.m. on August 15, 1982, two teenagers, Marilyn Green and her fiance Jerry Hillard, were shot and killed near a swimming pool in Washington Park on the south side of
Chicago. Anthony Porter, a 27-year-old gang member, was identified by several witnesses as being involved with the crime or near the crime scene. William Taylor, who had been swimming in the pool at the time of the shooting, initially said that he had not seen the shooting but had seen Porter run past shortly after the shots. He later said that he had seen Porter firing the shots. He was among six witnesses who identified Porter in the areas of the shooting, including one who said he had been robbed by Porter at gunpoint a short time earlier in the park. Police were given leads pointing toward other suspects. They appeared to pursue only Porter. Upon hearing that he was under suspicion, Porter went to the police and turned himself in. He was immediately arrested and charged with the two murders, one count of armed robbery, one count of unlawful restraint, and two counts of unlawful use of weapons. After a short trial, Porter was convicted of the murders. Judge Robert L. Sklodowski sentenced Porter to death, calling him a "perverse shark". An appeal to the
Illinois Supreme Court was denied in February 1986, and an appeal to the
United States Supreme Court was denied the following year. Porter continued to file appeals in the years that followed, delaying the execution. In 1995 Porter's defense counsel arranged testing of his client's mental capacity. He was found to have an
IQ of 51, characterizing him as
intellectually disabled. His counsel filed a new appeal on the grounds that Porter was incapable of understanding his punishment by the death penalty. In late 1998, forty-eight hours before he was scheduled to be executed, the court granted another stay. ==Northwestern University investigation==