Appeal from the Circuit Court of Cook County. Honorable Marcus R. Salone, Judge Presiding.
 The opinion of the court was delivered by: Presiding Justice Hoffman
 Following a bench trial, the defendant, Long Nhu Le, was convicted of criminal sexual assault and sentenced to a prison term of six years. On appeal, the defendant contends that: (1) his due process rights were violated when the trial court failed to allow an expert of his own choosing to examine the victim to determine whether she suffered from post-traumatic stress syndrome; and (2) the State failed to prove him guilty beyond a reasonable doubt. For the reasons which follow, we affirm.
 Prior to trial, the defendant was notified that the State intended to present expert testimony that the victim, Fausta V. (F.V.), suffered from post-traumatic stress syndrome. In response, the defendant filed a motion for the appointment of an expert, wherein he alleged that he was indigent and seeking the services of a psychiatrist to examine F.V. as to the issue of post-traumatic stress syndrome. The trial court granted the defendant's motion and appointed a psychologist from the Psychiatric Institute of the Circuit Court of Cook County (hereinafter "Forensic Services Clinic") to examine F.V. Following the examination, defense counsel argued that the psychologist had failed to follow certain protocol with respect to a psychological test performed on F.V., and had also improperly communicated with the State. To remedy the situation, the trial court appointed a second psychologist from the Forensic Services Clinic to examine F.V.
 The State presented the following evidence at trial.
 F.V. testified that, in January 1997, she was working as a cleaning person at an office building located in downtown Chicago. F.V. stated that the defendant worked as a security guard in the same building. According to F.V., on January 18, 1997, she was working the night shift and had encountered the defendant on numerous occasions that evening. At approximately 11:40 p.m., the defendant asked her if she had finished cleaning the 43rd floor. F.V. replied "no", and proceeded up to the 43rd floor. The defendant left to respond to a call on his radio.
 F.V. testified that she was vacuuming on the 43rd floor when she suddenly saw the defendant, who grabbed her by the hair and pushed her into an office. F.V. stated that she yelled "no, Lee", and attempted to get away from him, but was unable to do so because he was "very aggressive". According to F.V., the defendant closed the office door and pinned her up against a wall. The defendant then placed his hands over F.V.'s breast and started kissing her. During this time, F.V. continued to tell the defendant "no" and attempted to get him off of her. F.V. stated that the defendant tore her bra as the two of them struggled. The defendant then attempted to push F.V. onto a nearby desk. F.V., however, continued resisting and telling the defendant "no". F.V. stated that the defendant pushed her and eventually threw her onto the floor.
 According to F.V., while on the floor, the defendant got on top of her and attempted to take her pants off. F.V. again attempted to escape from the defendant's grasp, but to no avail. The defendant then rolled F.V.'s pants down to her ankles and had sexual intercourse with her. She testified that, when the defendant was finished, he got off of her, and said that he was "sorry" and that he loved her. F.V. stated that she ran out of the office toward the elevator. Shortly thereafter, the elevator arrived and her boss, Zenon Zandecki, who was standing inside, asked her what had happened. She first waited for the defendant to leave the floor and then told Zandecki that the defendant pulled her by the hair into a vacant office and then had sex with her. F.V. stated that she also spoke to Eric Riggins, the security supervisor, about the incident. F.V. was subsequently taken to the hospital, where she submitted to a physical examination.
 F.V. was questioned at length about her interactions with the defendant prior to the incident. F.V. described an incident which occurred approximately eight months earlier when the defendant grabbed and kissed her at work. F.V. further testified that the defendant had kissed her on another occasion while giving her a ride home.
 Zandecki testified that, around midnight, he went up to the 43rd floor and saw F.V. waiting for the elevator. According to Zandecki, F.V. stated that she needed to talk to him. He stated that she appeared nervous and afraid, and her hands were "shaking" at the time. F.V. asked Zandecki for an assurance that he was not going to fire her. She then told Zandecki that the defendant grabbed her by the hair, forced her into a vacant office, and had sexual intercourse with her. Zandecki testified that he directed her to go to the 38th floor and wait for him. During this time, Zandecki reported the incident to Riggins. Zandecki testified that the police later arrived at the scene. According to Zandecki, F.V. appeared to be crying as she was talking to one of the policemen.
 On cross-examination, Zandecki admitted that, a few years earlier, F.V. had received two complaints about her job performance. Zandecki also testified that, three years prior to the incident, F.V. was on probation for absenteeism. He stated, however, that F.V. was not on probation when the incident took place. Finally, Zandecki acknowledged that an employee could be disciplined for having sexual relations at the workplace.
 Riggins testified that he spoke to Zandecki about the incident and then went to talk to F.V. Riggins stated that F.V. looked "nervous, distraught, [and] upset" and appeared to be crying. F.V. showed Riggins a bruise she had sustained on her breast. On cross-examination, Riggins acknowledged that he did not know what caused the bruise. Riggins stated that, when he observed the bruise, he also noticed that one of F.V.'s bra straps was detached. He also observed a small scratch on F.V.'s hand. Riggins testified that when F.V. was talking to the police about the incident, she appeared nervous and her lips were "trembling".
 The State presented the testimony of Dr. Andioco Barron, who was qualified as an expert in the field of psychiatry. Dr. Barron testified that he first examined F.V. on February 11, 1997. Dr. Barron stated that F.V. was having anxiety, depression, and nightmares after the incident. Based upon a reasonable degree of medical and psychiatric certainty, Dr. Barron opined that F.V. was suffering from post-traumatic stress syndrome. On cross-examination, Dr. Barron admitted that his opinion was based upon his personal observations of F.V., and not on her prior medical records. He also acknowledged that he did not know if F.V. suffered from any symptoms of depression before the incident. Finally, Dr. Barron testified that he did not have F.V. complete any tests to determine whether she was "malingering."
 The State rested, and the defendant testified on his own behalf. His account of what transpired on January 18, 1997, differed significantly from F.V.'s version of events. According to the defendant, around 11:30 p.m., he went up to the 43rd floor to help F.V. turn off the lights. The defendant stated that F.V. was cleaning an office at the time. He began massaging her back, as he had done in the past. According to the defendant, "one thing led *** to another" and the two of them began kissing and holding each other. The defendant testified that F.V. opened his zipper and began massaging his penis, as he massaged her breast. The defendant stated that F.V. then pulled him down on top of her, pulled down her pants, and initiated sexual intercourse with him. After they finished, F.V. put her pants back on and left the office.
 The defendant denied using any force against F.V. or threatening her in any way. He also denied ripping her bra. The defendant stated that F.V. never said "no" during the incident or stated that she did not want to have sex with him. Finally, the defendant testified that he and F.V. had sexual intercourse ...