Appeal from the Circuit Court of Cook County Honorable William P. O'Malley, Judge Presiding.
 The opinion of the court was delivered by: Justice Karnezis
 Following a bench trial, the trial court convicted defendant Corey Braddock of solicitation of a sex act in violation of section 11-14.1(a) of the Illinois Criminal Code of 1961 (720 ILCS 5/11-14.1(a) (West 2002)) (Criminal Code) and sentenced him to six months' supervision.
 The court denied defendant's motion for a new trial and motion in arrest of judgment. Defendant appeals the denial of his posttrial motions, arguing that his conviction should be reversed because (1) section 11-14.1(a) is unconstitutional because it is overbroad and vague; (2) he was not proven guilty beyond a reasonable doubt; and (3) a fatal variance existed between the evidence presented and the charges in the complaint. We affirm.
 Defendant, a City of Chicago police officer assigned to the Internal Affairs Division (IAD), was arrested on September 24, 2003, for offering Johanna Kramp, an undercover Chicago police officer working a prostitution sting investigation, money in exchange for sex. Defendant was charged with "solicitation for prostitution in that he approached the complainant and offered $50.00 U.S.C. in exchange for the performance of sexual intercourse in violation of 720 ILCS 5/ 11-15(a)(1)." *fn1 At trial, over defendant's objection, the court allowed the State to amend the complaint to allege that defendant "committed the offense of solicitation of a sex act in that he approached the complainant and offered $50.00 U.S.C. in exchange for the performance of sexual intercourse, an act of sexual penetration as defined in 720 ILCS 5/12-12(f) in violation of 720 Illinois Compiled Statutes 5/11-14.1(a)." The court offered defendant a continuance in which to prepare his case given the amended complaint but defendant declined and elected to proceed to trial.
 At trial, Officer Kramp testified that, at approximately 3:40 a.m. on September 24, 2003, she was in civilian clothes working as a decoy in the 900 block of West Belmont Avenue in Chicago. She noticed the driver of a white Ford Explorer staring at her as he passed her three or four times at a reduced speed. She identified defendant as the driver. Defendant pulled his car into an alley, parked and got out of the car. He approached Officer Kramp and asked her whether she was looking for a date. She said she was and asked him what he was looking for. He replied that he was looking for sex. She understood "sex" to mean "an act of sexual penetration." Officer Kramp then asked how much money defendant had and he responded by asking how much she charged. When she said $30 or $40, he responded "fine, okay."
 Officer Kramp told defendant to meet her at 3229 Wilton in his car. Officer Kramp started walking through the alley to that location and defendant returned to his car. As he was driving through the alley, defendant stopped Officer Kramp again. Officer Kramp asked him whether he had the money and defendant told her not to worry about it, that he was a police officer and would not "fuck [her] around." He showed Officer Kramp his police star, told her he was with IAD and he was "just looking to get his nut off." From her experience working in plain clothes, Officer Kramp was familiar with the street terms used during the solicitation of prostitution and her only understanding of the term "get my nut off" was that it meant "an act that would cause him to ejaculate."
 Officer Kramp asked defendant to show her the money. He told her that he could go get money. He asked her whether she was at least 17 years old and whether she had a condom. When she replied that she was 23 and did have a condom, defendant left. Officer Kramp radioed her backup officers and arranged for help should the transaction occur. When defendant returned, she asked him again whether he had the money. "He indicated that he did have the money, $50, and showed [her] some money." Officer Kramp saw money in defendant's hand and told him to pull into a parking spot. She then gave the prearranged signal to her backup officers indicating that the transaction was complete. Defendant slowly drove past the parking spot but two backup officers in unmarked cars stopped him. This was the last contact Officer Kramp had with defendant. She wrote a summary of the events on the arrest report, stating that defendant asked for sex. She explained that "sex" is the same terminology as "sexual intercourse".
 Officer Ricardo Fernandez testified that he stopped defendant's car after he saw Officer Kramp give the signal. During the patdown, defendant stated that he was a police officer and asked that he be given a break. Officer Fernandez did not inventory defendant's wallet although that was standard procedure.
 After the close of the State's case, defendant moved for a directed finding, arguing that the State failed to prove the elements of the amended complaint because there was no testimony that defendant solicited or that Officer Kramp agreed to perform "sexual intercourse" as specified in the complaint. Defendant argued that the only testimony reference was to the generic term "sex," which could encompass a myriad of acts besides sexual penetration. The court agreed that the complaint was very specific in its allegation that defendant solicited "sexual intercourse, an act of sexual penetration" but stated that Officer Kramp testified that she understood the word "sex" to mean an act of sexual penetration and denied the motion.
 Defendant then testified. He was driving home at 3:40 a.m. from an investigation location which he could not disclose *fn2 when he saw a girl who looked "pretty young" standing on the street. He pulled over and asked whether he could help her with anything. She asked him whether he was looking for a date and he said he was not and that he would like to help her. He moved his car to Wilton at her behest. He told the girl about opportunities to get off the street and about Sister-to-Sister, a program to which he referred women in need of help. After she asked him again whether he was looking for a date, he told her that he was a police officer with IAD and terminated the conversation because she did not want help. Defendant denied driving by Officer Kramp multiple times, asking for sex, saying he wanted to "get [his] nut off," asking her age or whether she had a condom.
 In rebuttal, Officer Kramp testified that defendant never told her about Sister-to-Sister, alternatives to working on the street or anything other than what she had related earlier.
 Following closing argument, the court stated that it found Officer Kramp credible and that the State proved defendant guilty beyond a reasonable doubt. Defendant filed a motion for a new trial and a motion in arrest of judgment. The court denied the motions and sentenced defendant to six months ...