Here's the info, but they don't have to register as an offender unless convicted, and the longer after the incident, the harder it is to convict. Also, we don't do CA law, their laws may differ significantly.
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LA. CODE CRIM. PROC. art. 571.1 Time limitationfor certain sex offensesFor the following offenses committed against avictim under 17, 30-year time limit which begins to run when victim attains the age of18:• Sexual battery (§ 14:43.1)• Second degree sexual battery (§ 14:43.2)• Oral sexual battery (§ 14:43.3)• Felony carnal knowledge of a juvenile(§ 14:80)• Indecent behavior with juveniles (§ 14:81)• Molestation of a juvenile (§ 14:81.2)• Crime against nature (§ 14:89)• Aggravated crime against nature (§14:89.1)• Incest (§ 14:78)