Urinating in public is illegal in every state. Defendants may be charged under a law that specifically criminalizes the act, or the prosecutor may allege that the defendant presented a public nuisance or is guilty of disorderly conduct. A harsher approach is to charge defendants with indecent exposure or public lewdness, which are crimes that may require convicted defendants to register as a sex offender.
Many city and county criminal ordinances also prohibit public urination. A typical ordinance might prohibit urination "on any street, sidewalk, alley, plaza, park, beach public building or public facility, or any place open to the public or exposed to public view." An ordinance with this kind of wording prohibits urination even on private property, if it's visible from a public place.
For information on public lewdness, see our article on Public Lewdness.
California's law on urinating in public is covered in Public Urination In California.
State law usually classifies disorderly conduct and similar crimes as misdemeanors, which are less serious offenses than felonies. Penalties for a misdemeanor may include incarceration in county jail (for up to a year, except in Ohio, which allows misdemeanor sentences to extend to two years), payment of a fine, and community service. Penalties will be more severe if you've been convicted of prior offenses.
Violations of local ordinances are generally punishable by fines, community service, or both. Local governments set the amounts of the fines. A typical fine might be from $50 to $500, depending on the circumstances.
Laws prohibiting public urination may be relevant to drunk and carousing college students, but other than that, they rarely affect those who are adequately dressed, fed, and housed. The majority of the population is never painfully far away from restroom facilities, and even if they need to use restrooms that are "for customers' use only," they can usually walk right in, without fear of being stopped.
This is not true for the homeless, whose numbers are increasing as services to help them area diminishing. Add to that the impossibility of finding a public restroom in most American cities, and the notion that one "decides" to commit this crime becomes absurd. One either drops trou or messes oneself, with no chance to go home, clean up, and change clothes.
Breaking the law out of necessity has long been recognized as a defense in America and England. To be successful, the defendant must show that he acted to prevent a significant evil with no adequate alternative, that he didn't create a bigger danger than the one avoided, that he had a reasonable and good faith belief in the necessity, and the circumstances were such that he did not contribute significantly to the emergency. Necessity does not negate the criminality of the act, but represents a public policy decision, that society shouldn't punish the defendant despite evidence of the crime. In essence, the defense asks the judge or jury to balance two outcomes -- to weigh the harm to be avoided against the impact of the criminal act.
A homeless person who urinates in public might be able to satisfy the elements of a necessity defense. The "significant evil" could be avoided by deciding to neither eat nor drink; or to suffer the consequences of a full and bursting bladder. No civilized person would accept either alternative. A defendant might be able to show that there were no public restroom alternatives. Most defendants might also be able to prove that they did not contribute to the necessity—that they are not homeless by choice.
But satisfying the requirements of the defense is not enough—a defendant must also convince the judge or jury that the harm to the defendant had he followed the law would have been greater than the harm to society that resulted in his not doing so.
Prosecutors occasionally charge defendants with the crime of indecent exposure or public lewdness. If convicted, these defendants face the onerous duty of registering as sex offenders, a sentence that will follow them for the rest of their lives. Several states allow for such registration, including Arizona (involving minors and repeat crimes), Ariz. Rev. Stat. §13-3821; California, Cal. Penal Code § §314(1)-(2), 290; and Georgia (when done in view of a minor) Ga. Code Ann. § §42-1-12, 16-6-8.
If you've been charged with public urination, do not dismiss it as an inconsequential matter. A conviction for lewd conduct or disorderly conduct can have consequences, especially if you are charged again for such a crime and have this on your record. Consider consulting with an experienced, local criminal defense attorney, who will know how such cases are typically handled in the court that will hear your case, and can advise you as to your options. Never speak with the prosecutor or a prosecutor's investigator without having your lawyer at your side.