Appellant William Santos, a convicted sexual offender, appeals from the trial court’s denial of his motion to quash an indictment charging him with failure to register a new residence address as required under OCGA § 42-1-12, Georgia’s sex offender registration law. He contends OCGA § 42-1-12 is unconstitutional on numerous grounds, including that the statute’s registration requirements are unconstitutionally vague in their application to the homeless. After reviewing the challenged language of the statute, we agree that OCGA § 42-1-12 does not give homeless sexual offenders without a residence address fair notice of how they can comply with the statute’s registration requirement, and therefore, we reverse.
1. The Due Process Clause requires that the law give a person of ordinary intelligence fair warning that specific conduct is forbidden or mandated. United States v. Harriss, 347 U. S. 612, 617 (74 SC 808, 98 LE 989) (1954); Hall v. State, 268 Ga. 89, 92 (485 SE2d 755) (1997). Vagueness may invalidate a criminal law on either of two bases: a statute may fail to provide notice sufficient to enable ordinary people to understand what conduct it prohibits or requires, or the statute may authorize and encourage arbitrary and discriminatory enforcement. City of Chicago v. Morales, 527 U. S. 41, 55 (119 SC 1849, 144 LE2d 67) (1999); Roemhild v. State, 251 Ga. 569 (2) (308 SE2d 154) (1983). Vagueness challenges to criminal statutes that do not implicate First Amendment freedoms must be examined *515in the light of the facts of the case to be decided. United States v. Mazurie, 419 U. S. 544, 550 (95 SC 710, 42 LE2d 706) (1975); Thelen v. State, 272 Ga. 81 (526 SE2d 60) (2000).
OCGA § 42-1-12 requires convicted sexual offenders to register with the sheriff of the county in which they reside and to maintain with the sheriff certain required registration information, including the address of the sexual offender’s residence. OCGA § 42-1-12 (a) (16); OCGA § 42-1-12 (f) (2), (3). Sexual offenders must update the required registration information within 72 hours of any change. However, if the information is the sexual offender’s new residence address, the sexual offender must give the required information to the sheriff of the county with whom the sexual offender last registered within 72 hours prior to any change of residence address and to the sheriff of the county to which the sexual offender is moving within 72 hours after establishing the new residence. OCGA § 42-1-12 (f) (5). OCGA § 42-1-12 (a) (1) defines the term “address” as “the street or route address of the sexual offender’s residence” and specifically states that for purposes of the Code section, “the term does not mean a post office box, and homeless does not constitute an address.”
Here, it is undisputed that Santos is a sex offender required to register pursuant to OCGA § 42-1-12. In 2006 he registered with the Hall County Sheriffs Office indicating his residence address as the Good News at Noon homeless shelter in the city of Gainesville. In July 2006 he was asked to leave the shelter by shelter officials. He left the shelter on or about July 19, 2006 and was homeless until his arrest in Hall County on October 19, 2006. The parties stipulated that during the period from July 19, 2006 to his October 2006 arrest, Santos did not possess a street or route address that complied with the requirements of OCGA § 42-1-12 (a) (1). The State charged Santos with three counts of failure to register under OCGA § 42-1-12, alleging that he failed to register a new address with the Hall County Sheriff within 72 hours prior to leaving the Good News at Noon shelter for the last time. Santos filed a motion to quash the indictment, asserting inter alia, that OCGA § 42-1-12 failed to provide proper notice of what conduct is required of a homeless offender who lacks a street or route address and that this lack of direction leads to arbitrary and discriminatory enforcement.
Since this case must be decided on its facts, the question is whether the reporting requirements of OCGA § 42-1-12 provided sufficient notice to Santos of what conduct was mandated by the statute when he left his previous residence address, the Good News at Noon shelter, but possessed no new permanent or temporary residence with a street or route address. According to its plain language, OCGA § 42-1-12 mandates that offenders register a change *516of residence by providing the sheriff of their county a specific street or route address. The statute, however, contains no objective standard or guidelines that would put homeless sexual offenders without a street or route address on notice of what conduct is required of them, thus leaving them to guess as to how to achieve compliance with the statute’s reporting provisions. Compare California, Cal. Penal Code § 290.011 (a) and (d) (transient offenders must register every 30 days and report all “places where he or she sleeps, eats, works, frequents, and engages in leisure activities”); Illinois, § 730 ILCS 150/6 (offender who lacks fixed residence must report weekly, in person, to law enforcement agency where offender is located); Kentucky, KRS § 17.500 (7) (defining residence as “any place where a person sleeps”); Minnesota, Minn. Stat. § 243.166, Subd. 3a (offenders without primary residence must register within 24 hours after leaving former primary residence and must report by describing “the location of where the person is staying”); and Washington, Wash. Rev. Code 9A.44.130 (3) (b) (requiring homeless offender who lacks fixed residence to register place where offender plans to stay). In the absence of any language in the statute providing direction or a standard of conduct applicable to offenders who do not possess a street or route address, we conclude that OCGA § 42-1-12 does not provide fair warning to persons of ordinary intelligence as to what is required to comply with the statute, and therefore, the registration requirement as applied to Santos is unconstitutionally vague. See Thelen, supra, 272 Ga. at 82; Hall, supra, 268 Ga. at 92.
The State argues that OCGA § 42-1-12 should be interpreted to allow homeless offenders with no street or route address to register an “address” by providing the geographic location at which they may be located or a more general description of their temporary residence. Such an argument would be more compelling had the Georgia legislature not defined the term “address” to require offenders to specifically report a “street or route address” and further emphasizing that “homeless does not constitute an address.”1 Moreover, even if we were to adopt the State’s interpretation of OCGA § 42-1-12, the statute still would be unconstitutionally vague because it fails to provide clear guidelines to authorities charged with its enforcement regarding what specific information the offender is required to report. “The penalties of the law cannot rest upon subjective guidelines. [Cit.] The language of a criminal ordinance *517cannot be so ambiguous as to allow the determination of whether a law has been broken to depend upon the subjective opinions of complaining citizens and police officials. [Cits.]” (Punctuation omitted.) Thelen, supra, 272 Ga. at 83.
Accordingly, we find the challenged registration requirement is too vague to be enforced against Santos and is, therefore, unconstitutional under the due process clauses of the Georgia and United States Constitutions. We are by no means holding that all homeless sex offenders are exempt from the statute’s reporting requirements. Our decision renders unconstitutional the address registration requirement as applied to homeless sex offenders who, like Santos, possess no street or route address for their residence. It does not exempt such offenders from reporting other information required under the statute and it does not exempt homeless sex offenders who are able to provide a street or route address, such as the address of a shelter at which they are staying.
2. Our holding in the above division renders consideration of Santos’ other constitutional challenges to the statute unnecessary.
Judgment reversed.
Ml the Justices concur, except Carley, J., who dissents.In seeming recognition that some sexual offenders may not possess an “address,” the legislature provided specific guidelines to be followed in the event a sexual offender resides in a motor vehicle, trailer, mobile home or vessel. OCGA § 42-1-12 (a) (16). The statute contains no similar guidelines informing offenders how to comply with the reporting requirements if they have no street or route address and do not reside in one of the enumerated objects.