The opinion of the court was delivered by: Justice Miller
After a jury trial in the circuit court of Cook County, the defendant, Anthony Brown, was convicted on two counts of first degree murder and on one count each of aggravated vehicular hijacking, aggravated criminal sexual assault, and armed robbery. The defendant waived his right to a jury for purposes of a death penalty hearing, and, following a hearing, the trial Judge sentenced the defendant to death for the convictions for first degree murder. The Judge sentenced the defendant to concurrent 30- year terms of imprisonment for his convictions for aggravated criminal sexual assault and aggravated vehicular hijacking; the Judge did not impose any sentence for the armed robbery conviction, finding that it merged with that for vehicular hijacking. The defendant's execution has been stayed pending direct review by this court. Ill. Const. 1970, art. VI, §4(b); 134 Ill. 2d Rs. 603, 609(a). For the reasons set forth below, we affirm the judgment of the circuit court.
The following evidence was presented at trial. We will describe this testimony in detail, in light of the defendant's challenge to the sufficiency of the evidence. Steven Fitch testified that on January 12, 1994, he, Reginald Wilson, and Wilson's girlfriend, Felicia Lewis, were driving in Wilson's Chevrolet Blazer. They stopped at a gas station so that Fitch and Wilson could use the restroom. When Fitch returned to the Blazer, he saw a person in the doorway on the passenger side of the vehicle; the person was letting someone else in the back. Fitch could see that the person standing outside the vehicle was not Wilson. As Fitch walked toward the Blazer, the person standing outside the vehicle asked Fitch what he was looking at. Fitch did not reply. He saw someone other than Wilson sitting in the driver's seat of the Blazer.
Fitch returned to the gas station, but the door was locked. The Blazer then drove off. Fitch ran across the street to a telephone to call the police. When the police arrived, Fitch reported what had happened, and he rode with the police to look for the Blazer. Wilson had a pager with him, so Fitch tried to call his friend on the pager throughout the night. Fitch did not receive any response, however.
On January 13, Fitch went to the Sauk Village police station and spoke with officers there. Later, Fitch went to Area One headquarters and talked to detectives. At Area One Fitch also viewed a lineup, and he identified the person whom he had seen standing outside the passenger side of the Blazer.
Zarice Johnson, a co-defendant, also testified on behalf of the prosecution at the defendant's trial. Johnson, 26 years old at the time of trial, described the commission of the offenses in this case. On January 12, 1994, the defendant came to Johnson's apartment around 10 or 10:30 p.m. They then left together, in the defendant's car, a two-door Chevrolet Caprice. Three other persons-Scott Chambers, Stanley Hamelin, and Carl Williams-were already in the vehicle. The defendant drove around awhile, and Hamelin suggested that they steal a vehicle. The defendant agreed to that plan. They located a vehicle and parked near it, but they later changed their minds when they saw the number of persons in it.
The defendant then drove to a gas station located at 79th Street and the Dan Ryan expressway. Hamelin got out of the car to purchase gas; as he tried to close the car door, it swung open; the defendant became upset and said that anyone walking by could see a gun, a 9-millimeter pistol, that was sitting on the front seat of the car. The defendant then closed the car door. Hamelin bought gas and returned to the car. As they were leaving the station, they noticed another vehicle pulling in, and someone commented about the rims on it. Hamelin told the defendant to pull over so that he could get out. The defendant did so, and Hamelin, Chambers, and Williams then got out of the car and went back to the gas station. Johnson saw Chambers get into the vehicle, a Blazer. Hamelin stood by the passenger side; Johnson did not notice what Williams was then doing. Johnson next saw a person approach the passenger side of the Blazer and then walk back to the gas station fast, as though he was trying to get in the building. Johnson later saw the same person walk back to the side of the service station and climb a fence.
The defendant then drove his car around the block and returned to the gas station. Johnson could see Chambers and Hamelin, but not Williams. Chambers was standing on the driver's side, and Hamelin was on the passenger side of the Blazer. They got in the Blazer and it then drove off, following the defendant's Caprice. Johnson was seated in the back seat of the Caprice. The defendant drove the Caprice to the Dan Ryan expressway and drove north to 71st Street, where the defendant pulled to the side of the highway. The Blazer pulled off the road too and parked in front of the Caprice. The defendant got out and walked to the Blazer. Johnson stayed in the Caprice and therefore could not overhear the defendant's conversation with the occupants of the Blazer. After several minutes, the defendant returned to the Caprice and said that a man and a pretty woman were in the Blazer. The defendant then drove off, continuing northbound on the Ryan.
The defendant left the expressway at 43rd Street and drove to 47th and Vincennes. There, the defendant pulled into a parking lot and directed the Blazer where to park. The defendant got out of the Caprice and talked to Hamelin and Williams. Johnson was still seated in the back of the Caprice, but he could hear their conversation because the car door was open. The defendant asked the others if there was any "loot" in the Blazer. Stanley Hamelin mentioned a car alarm and stereo, and Carl Williams mentioned a CD player. The defendant also asked whether there was any money, and neither one responded immediately. The defendant then got back in the Caprice, and Stanley Hamelin walked over and handed the defendant a bundle of money, which the defendant put in his pocket. Hamelin also showed the defendant a ring he had taken, and Hamelin then put it back in his pocket.
The defendant said that he was going to make the woman perform oral sex on him; the defendant was laughing while he said this. The defendant went to the Blazer and told the woman to get out, and he directed Johnson to move to the front seat of the Caprice. Johnson moved to the front passenger seat, and Hamelin handed him a Kenwood stereo and a portable CD player taken from the Blazer. The defendant then put the woman in the back seat of the car and got in. After the act of oral sex, the defendant told the woman to remove her pants; she was crying, and Johnson told her to stop crying and to cooperate with the defendant. The woman then said that she had had a baby in November and that she was having her period. The defendant said the woman was lying, and she replied that she was wearing a sanitary pad. The defendant then told the woman to place her coat on the car seat, and he started having sex with her. Later, he told her to perform oral sex again. While they were in the car, the defendant forced the woman to submit to several acts of sexual intercourse.
The defendant instructed Hamelin and Chambers to keep the victims in the Blazer until the defendant returned, after he could locate a place to kill the victims. The defendant, Carl Williams, and Johnson then drove off in the Caprice. The defendant drove around the area where they had parked. The defendant later parked the car and walked back toward the Blazer with Carl Williams. The defendant looked at the Blazer, which was across the street, and then returned to the Caprice. The defendant was upset and said that he did not know why the victims had been killed in the Blazer and then left there sitting up. The defendant told Johnson to drive the defendant and Williams to the defendant's home, at 38th and Vincennes.
Johnson, the defendant, and Williams later met Hamelin and Chambers at Hamelin's sister's apartment. The defendant asked them why they had shot the victims in the Blazer. Hamelin responded that they did not kill the victims there, and he explained that he and Chambers had made the victims get out of the vehicle, had walked them to a dumpster, and had made them climb into it. Chambers then shot the man in the head once; the woman started screaming and put her hands up, and Chambers reached up under her arm and shot her twice. They then walked off, and Hamelin told Chambers that he was "bogus" because he had shot the woman twice and the man once-so Chambers returned to the dumpster and shot the man in the head again.
According to Johnson, the defendant that evening gave each of the offenders a part of the money taken in the crimes. They later returned to the Blazer and found about 20 to 25 compact discs and cassette tapes, which Chambers put in a plastic bag and gave to the defendant. Chambers then said that he wanted to take a large stereo speaker to Johnson's house, and they then did that.
The defendant returned to Johnson's apartment a couple hours later. Johnson and his cousin then left with the defendant, in the defendant's Caprice. Johnson noticed that the Blazer was parked behind the defendant's car, and that the Blazer contained Hamelin and Chambers. They got on the Dan Ryan expressway, with the Blazer following the defendant's car, and drove to Sauk Village; Williams was not with them. After parking at a McDonald's restaurant, the defendant gestured for Chambers and Hamelin to get in the Caprice, and they did. Later, Chambers and Hamelin drove off in the Blazer. They came back several minutes later, pursued by the police. Hamelin jumped out of the Blazer and tried to run; a female officer stopped her car, got out, and chased him. Hamelin fell, and the officer arrested him. Johnson, his cousin, and the defendant then drove back to Chicago in the defendant's Caprice. Johnson was with the defendant again during the night of January 13, 1994, and they were arrested at that time. They were taken to a police station, and Johnson was questioned about the offenses. Johnson explained to the jury that he was charged in this case and that he later entered into a plea agreement. The agreement required Johnson to plead guilty to one count each of first degree murder, criminal sexual assault, armed robbery, and vehicular hijacking. In exchange for his truthful testimony, the State would recommend a 35-year sentence. Johnson said that he would be eligible for release after 17½ years if he received day-for-day good-time credit on his sentence. Johnson also said that he had lived in the witness protection program in the county jail for the five months preceding his testimony. On cross-examination, Johnson acknowledged that he initially denied his involvement in these offenses when police questioned him.
A nearby resident, Clemon Cunningham, discovered the victims' bodies around noon on January 13. Cunningham reported his discovery to the police, who then began an investigation. One of the officers responding to that call, James Hogan, a forensic investigator for the Chicago police department, testified that on the afternoon of January 13, 1994, he went to 4800 S. Vincennes to investigate a report of two bodies found in a dumpster. Hogan photographed the bodies and gathered up four cartridge cases. The cartridge cases were stamped "9 mm Win"; two of them were lying at the bottom of the dumpster, and two were lying on the chest of the male victim.
Mark DiSanto, a Sauk Village police officer, testified that on the morning of January 13, 1994, he received an assignment to check on a suspicious vehicle. Officer DiSanto went to the area, which was residential, and found a black Blazer parked with its engine running. DiSanto parked behind the vehicle and walked up to it, and the Blazer then speeded away. DiSanto followed the Blazer, which traveled a distance of about four or five houses and later came to a stop on a nearby lawn. The driver and a passenger jumped out of the vehicle and ran off in different directions. DiSanto chased the driver, Scott Chambers, and apprehended him. Another officer later arrived, and DiSanto saw that she already had the Blazer's passenger, Stanley Hamelin, in her squad car.
Edward Winstead, a Chicago police detective, testified that on the afternoon of January 13, 1994, he and his partner went to the place where the victims' bodies had been discovered. Winstead and the others removed the bodies from the dumpster. The female victim had a bra entwined in her hands. A photo identification card disclosed her identity as Felicia Lewis. No identification could be found on the male victim. The officers later went to the address on the woman's ID card. Later that afternoon Officer Winstead went to Sauk Village; other detectives from Chicago were also there. Winstead spoke with the victims' friend Steven Fitch at the Sauk Village police station. Winstead testified that Fitch later viewed a lineup containing Chambers, Hamelin, and five other persons. Fitch identified Hamelin as the person he had seen getting into the Blazer.
Other testimony revealed that the defendant had about $500 or $510 in cash with him at the time of his arrest on January 13. Investigators later recovered a number of items from the defendant's Caprice, including videotapes, compact discs, cassette tapes, a Kenwood stereo, a Panasonic CD player, and an adapter.
Investigators examined the defendant's Caprice and Reginald Wilson's Blazer for fingerprints and searched the vehicles for other evidence. Investigators lifted three prints from various places inside the Caprice. They found an earring stud on the seat, a cassette radio in the trunk, and a glove and a stocking cap. They also inspected the Blazer. There, the only fingerprint impression they could find was on a compact disc. They also found an earring, a plastic camera, an instruction manual for a Kenwood stereo, a Kenwood storage case, a Panasonic CD player case, and various cards and papers.
Pamela Fish, employed at the time of the investigation by the Chicago police department crime laboratory, testified that on January 18, 1994, she examined evidence from this case. Fish stated that swabs taken from the female victim were all negative for the presence of semen. Fish explained that this was not unusual, and that half of these are negative. Fish determined that Felicia Lewis' blood type was type O. Fish also tested seat cushions taken from the Caprice and found a small area that tested positive for human blood. Its small size, however, precluded further testing. Fish said that the spot appeared to be a smear-type stain and that it could have been placed there by a person's hands.
Fish also found a reddish-brown stain the size of a nickel inside the underwear the defendant was wearing at the time of his arrest in this case. Fish concluded that this was a smear stain and was a mixture of human blood and seminal material. She later tested the defendant's blood type and found that it was type O, and she also obtained genetic markings from blood samples taken from the defendant and Felicia Lewis. Fish attempted to test the underwear stain for genetic markings but was unable to obtain any results. She explained that the inability to obtain a typing result from a stain is generally the consequence of two possible causes: that the sample is too small, or that the DNA material in the stain has degraded. On cross-examination, Fish stated that half the population in the United States has type O blood. She could not determine when the blood was placed on the car seat or when the stain was placed in the underwear.
Dr. Barry Lifschultz, a staff pathologist with the Cook County medical examiner's office, performed autopsies on the two victims. In examining Reginald Wilson, Dr. Lifschultz found a number of gunshot wounds. Two were located on the victim's head. One of these was an entrance wound to the right top of the head, and there was an exit wound in the left neck. Also, there was an entrance wound on the right side of the head above the ear, and an exit wound on the victim's face. Dr. Lifschultz also found a gunshot would to the upper left chest, and a bullet was lodged in the victim's chest. In addition, Dr. Lifschultz found a gunshot wound to the upper front part of the left arm, and a bullet was lodged in the elbow of the left arm. Dr. Lifschultz stated that the nature of this wound suggested that the bullet had traveled through something else before striking the arm, and he explained that the bullet could have passed through the head and then into the chest. Dr. Lifschultz concluded that the cause of death was multiple gunshot wounds.
In his examination of Felicia Lewis, Dr. Lifschultz found four gunshot wounds on her. An entrance wound was on the back of the lower part of the left arm, and there was a corresponding exit wound on the lower part of the arm. Dr. Lifschultz also found an entrance wound on the lower part of the arm, which exited on the inner part of the same arm. Dr. Lifschultz found two other gunshot wounds, and both of these were to the head. One was an entrance wound to the right side of the head, and he recovered a bullet from the jaw. Another entrance wound was to the middle part of the face, and the bullet from this wound was lodged in the upper left chest. Dr. Lifschultz stated that the wounds to the victim's arms were consistent with a person trying to shield herself. Dr. Lifschultz concluded that the cause of the victim's death was multiple gunshot wounds. A sanitary napkin was recovered from the victim, and swabs were taken of the victim's oral, vaginal, and rectal cavities. Dr. Lifschultz did not find any evidence of trauma to the victim's genital area.
The defense presented testimony from two witnesses. The first witness called by the defense was Richard McGrath, a Chicago police officer who worked as a latent fingerprint examiner. McGrath stated that he was not able to match any of the latent prints taken from the Caprice with the defendant's known fingerprint standard. On cross-examination, McGrath stated that the three prints from the Caprice did not match those of the defendant, Zarice Johnson, Scott Chambers, Stanley Hamelin, or Carl Williams. Felicia Lewis' fingerprints were found on a pill container and on a makeup case found in the Blazer. One of Reginald Wilson's prints was on an insurance document found in the Blazer, and also on a birth certificate found in the Blazer. McGrath was not able to match some of the prints with anyone. He said that it was not surprising that a car owner would not leave any latent prints in his own car, for the owner would be touching things repeatedly and would not leave clear impressions.
Also called as a witness by the defense was Scott Rochowicz, of the microscopic trace evidence unit of the Chicago police department crime laboratory. Rochowicz testified that in June 1994, he examined all the hair evidence in the case and compared it with samples taken from the defendant and from Felicia Lewis. Rochowicz found that the hairs recovered from Felicia Lewis' clothing were similar to her own hairs, and that the hairs recovered from the defendant's clothing ...