In People v. Hofsheier (2006) 37 Cal.4th 1185, the Court held that "In its present form, Penal Code section 288a provides a graduated scale of punishment depending on the age of the parties and the presence or absence of force or other coercion." (People v. Hofsheier, supra, 37 Cal.4th at p. 1194.) The governing portion of the statute is subdivision (b)(1). Under that provision, "any person who participates in an act of oral copulation with another person who is under 18 years of age shall be punished by imprisonment in the state prison, or in a county jail for a period of not more than one year." ( 288a, subd. (b)(1).) The statute imposes a "mandatory registration requirement for ... voluntary acts of oral copulation when the victim is 16 or 17 years of age." (People v. Hofsheier, supra, 37 Cal.4th at p. 1194.) Section 261.5 "prohibits 'unlawful sexual intercourse,' defined as an act of intercourse with a minor 'not the spouse of the perpetrator.' ( 261.5, subd. (a).) Like section 288a (b)(1), section 261.5 also has a graduated scale of punishments." (People v. Hofsheier, supra, 37 Cal.4th at p. 1194.) In Hofsheier, the pertinent part of the statute is subdivision (c). "Subdivision (c) states that any person who engages in an act of unlawful sexual intercourse with a minor more than three years younger than the perpetrator is guilty of either a misdemeanor or a felony." (Ibid.) A person convicted under that subdivision "would not face mandatory sex offender registration." (Id. at p. 1195.) "Section 290 requires anyone convicted of certain sex offenses to register for life as a sex offender." (People v. Hofsheier, supra, 37 Cal.4th at p. 1195.) For the listed offenses, registration is mandatory. (Ibid.) The requirement "cannot be avoided through a plea bargain or through the exercise of judicial discretion." (Id. at p. 1196.) The specifically enumerated offenses include section 288a, oral copulation with a minor. ( 290, subd. (a)(2)(A); see People v. Hofsheier, supra, 37 Cal.4th at p. 1195.) Thus, conviction of that offense results in mandatory lifetime registration for the offender. By contrast, the list of offenses does not include section 261.5, unlawful intercourse with a minor. (See People v. Hofsheier, at p. 1195.) Section 290 thus does not subject those convicted of that offense to mandatory registration. (See 290, subd. (a)(2)(A); Hofsheier, at p. 1195.) But it does give the trial court discretion to order them to register as sex offenders. ( 290, subd. (a)(2)(E); see Hofsheier, at pp. 1196-1197.) "Section 290, subdivision (a)(2)(E) ... provides that a person convicted of 'any offense not included specifically in section 290' may be required to register 'if the court finds ... that the person committed the offense as a result of sexual compulsion or for purposes of sexual gratification.' If it requires registration, the trial court must 'state on the record the reasons for its findings and the reasons for requiring registration.' " (People v. Hofsheier, supra, 37 Cal.4th at p. 1196.) The statute thus "gives the trial court discretion to weigh the reasons for and against registration in each particular case." (Id. at p. 1197.) A conviction for unlawful sexual intercourse under section 261.5 exposes the defendant to discretionary registration only. But "a person convicted of voluntary oral copulation with a minor under section 288a (b)(1)" is subject to mandatory lifetime registration, which cannot be avoided "either through a plea bargain or through the exercise of judicial discretion." (People v. Hofsheier, supra, 37 Cal.4th at p. 1197.)