Because a person convicted of indecent exposure (Pen. Code, sec. 314, subd. (1)) is not similarly situated to one convicted of lewd conduct (sec. 647, subd. (a)), mandatory sex registration for section lewd conduct, as compared to discretionary registration for indecent exposure does not violate equal protection. Appellant entered a sauna at a health club where another club member was sitting. When the man looked up, he saw appellant smiling at him and masturbating. As a result of the conduct, a jury convicted appellant of lewd conduct and indecent exposure. Appellant was granted informal probation with lifetime registration as a sex offender, based on the indecent exposure conviction. On appeal, he argued that the registration requirement was unconstitutional because the same conduct underlay both offenses, but there is no mandatory registration for lewd conduct. The appellate court disagreed, noting that the nature of specific intent for indecent exposure is distinct from that involved with lewd conduct, the former involving purposeful intent whereas lewd conduct can be the result of the participant’s reckless behavior in a public place, i.e., not knowing others can see the offensive behavior. This different intent element is a sufficient basis for finding, for the purposes of registration, that persons convicted of one are not similarly situated with persons convicted of the other. Additionally, the statutes differ in where the crimes can occur. Lewd conduct always occurs in a public place, whereas indecent exposure can be in any place where others are present who can be offended.