Appeal from the Circuit Court of Cook County. Honorable Ralph Reyna, Judge Presiding.
 The opinion of the court was delivered by: Justice South
 This appeal arises from defendant's conviction for aggravated unlawful use of a weapon (UUW) (720 ILCS 5/24-1.6(a)(1), (a)(3)(A) (West 2000)) following a jury trial. Defendant was sentenced to Cook County boot camp.
 At trial, Chicago police officer Alan Hadac testified that for the past three years he had been assigned to the Chicago Housing Authority (CHA) and worked at a police building located at 365 West Oak Street, which is part of the Cabrini Green housing complex. He described the duties of a Chicago police officer assigned to CHA public housing as being "strictly assigned to patrol housing sites federally funded throughout *** Chicago, whether it be Cabrini Green, Rockwell Gardens, Robert Taylor."
 In the early morning hours of July 30, 2001, Officer Hadac was standing in a large parking lot behind 365 West Oak, commonly referred to as the "Blacktop," where police officers often parked their vehicles. The Blacktop was bordered by four buildings and a youth center. Two of the buildings, 911-23 Sedgwick Avenue and 929-939 Hudson Avenue, are CHA buildings. According to Officer Hadac, the CHA had recently installed new lighting in the area. As he conversed with Officers Simon, McCormick and Carroll, Officer Hadac heard gunfire and turned to look in the direction of where the shots had been fired. He saw defendant standing at the rear of 929 Hudson with his right arm extended and a gun in his hand. Defendant fired the weapon several times. Officer Hadac ran towards defendant, who went into 929 Hudson, while Officers McCormick and Carroll entered a nearby vehicle.
 A chase ensued when defendant ran through the building at 929 Hudson and out onto the street. As defendant and Officer Hadac turned the corner onto Locust Street, Officer Hadac observed defendant toss the gun over a nearby fence. Hadac alerted Officers McCormick and Carroll that he had seen defendant throw the weapon to the ground and continued his pursuit until he apprehended him as he was attempting to enter an apartment on the seventh floor of the CHA building at 939 Hudson Avenue.
 Chicago police officer Thomas Carroll testified that he also worked out of the CHA police district at 365 West Oak. He corroborated Officer Hadac's testimony regarding the events surrounding the firing of the gun and the subsequent apprehension of defendant.
 Chicago police officer Brennan McCormick testified that on the morning of July 30, 2001, he was in the CHA parking lot behind 365 West Oak with two CHA police officers when he heard gunshots. He observed defendant "with a gun in his hand outside of the housing project [at] *** 929." Officer McCormick identified defendant as the shooter and subsequently recovered a 9-millimeter automatic weapon that defendant had thrown to the ground.
 At the conclusion of the trial, the jury found defendant guilty of aggravated UUW and he was sentenced to Cook County boot camp.
 On appeal, defendant has raised the following issues for our review: (1) whether he was proven guilty of the offense beyond a reasonable doubt; (2) whether the penalty for aggravated UUW is unconstitutionally disproportionate to the penalty for UUW; (3) whether the aggravated UUW statute violates due process by allowing a felony conviction based upon innocent conduct; and (4) whether the aggravated UUW statute violates due process and equal protection in the absence of a rational basis to differentiate between property owners and renters.
 Defendant initially contends that his conviction for aggravated UUW must be reversed because the State failed to prove an essential element of the offense, i.e., that he was not on his own land at the time that he possessed the firearm.
 When a defendant challenges the sufficiency of the evidence, the question on review is whether, after viewing the evidence in the light most favorable to the State, any rational trier of fact could have found the essential elements of the offense beyond a reasonable doubt. People v. Smith, 185 Ill. 2d 532, 541 (1999). A court of review may not substitute its judgment for that of the trier of fact and will not reverse a conviction unless the evidence is so unsatisfactory that it creates a reasonable doubt as to the defendant's guilt. People v. Lundy, 334 Ill. App. 3d 819, 825 (2002).
 The aggravated UUW statute provides, in pertinent part:
 "(a) A person commits the offense of aggravated unlawful use of a weapon when he or she knowingly:
 (1) Carries on or about his or her person or in any vehicle or concealed on or about his or her person except when on his or her land or in his or her abode or fixed place of business any pistol, revolver, stun gun or taser or other firearm; *** ***; and
 (3) One of the following factors is present:
 (A) the firearm possessed was uncased, loaded and immediately accessible at the time of the offense[.]" (Emphasis added.) 720 ILCS 5/ 24-1.6(a)(1), (a)(3)(A) (West 2000).
 As the above-italicized exception exists as part of the body of this offense, the State bears the burden of disproving beyond a reasonable doubt the existence of this exception in order to sustain the defendant's conviction. People v. Laubscher, 183 Ill. 2d 330, 335 (1998). In meeting this burden, the State may rely upon circumstantial evidence if it provides proof beyond a reasonable doubt that the defendant was not on his land or in his abode or fixed place of business at the time of the offense. Laubscher, 183 Ill. 2d at 335. However, there must be some evidence to create a reasonable inference that the exception exists as the State may not leave essential elements of the offense to conjecture or assumption. Laubscher, 183 Ill. 2d at 335-36.
 In Laubscher, a case relied upon by defendant, the complainant and defendant resided in different units of the same apartment building. Laubscher, 183 Ill. 2d at 333. The defendant, who had a gun on his person, had an argument with two men on the lawn area of the apartment complex. Laubscher, 183 Ill. 2d at 333-34. The complainant intervened and seized a handgun from the defendant's waistband, the police were called, and defendant was arrested. Laubscher, 183 Ill. 2d at 333-34. The supreme court affirmed the appellate court's reversal of the defendant's UUW conviction after concluding that there was no evidentiary basis for the trial court to infer that the defendant did not have an ownership interest in the premises. Laubscher, 183 Ill. 2d at 336. Although the complainant loosely referred to occupants of the building as " 'tenants,' " the only evidence offered by the State of the defendant's connection with the property was that he " 'lived in the building.' " Laubscher, 183 Ill. 2d at 336. That evidence was insufficient to establish beyond a reasonable doubt the defendant's particular interest in the premises. Laubscher, 183 Ill. 2d at 336. The supreme court affirmed the appellate court's finding that "although it was not unreasonable for the trial court to assume defendant had no ownership interest in the premises, permitting such an inference without any evidentiary basis would effectively shift the burden to defendant to prove that he was on his land." Laubscher, 183 Ill. 2d at 336.
 Applying the principles set forth above, we find that the State presented sufficient evidence to establish that defendant was not on his own land at the time of the offense. Officers Hadac and Carroll, both assigned to the CHA for a period of years, testified that defendant was standing at 929 Hudson when he fired several shots from a gun. Defendant subsequently ran through 929 Hudson with the gun in his hand and was ultimately apprehended when he attempted to gain access to an apartment on the seventh floor of the CHA building located at 939 Hudson. Unlike in Laubscher, Officer Hadac specifically identified the premises at 929 and 939 Hudson as CHA buildings. Officer Hadac further testified that he was assigned to a nearby police station which was part of a CHA public housing complex and described for the jury the duties of a CHA police officer as being responsible for "strictly patrolling federally funded housing sites." Moreover, Officer McCormick testified that defendant was standing ...