In Philippine criminal law, the "prescription of a crime" refers to the loss of the State's right to prosecute an offender due to the lapse of a certain period of time fixed by law. For victims and practitioners alike, understanding these timelines is critical, as filing a complaint beyond the prescriptive period results in the permanent dismissal of the case.

1. Classification of the Offense

To determine the prescriptive period, one must first look at the penalty attached to the crime under the Revised Penal Code (RPC). Acts of Lasciviousness is punished under Article 336:

Penalty: Prision correccional (ranging from 6 months and 1 day to 6 years).
Classification: Because the penalty is prision correccional, it is classified as a correctional penalty.

2. The Prescriptive Period

Under Article 90 of the Revised Penal Code, the periods for the prescription of crimes are as follows:

Crimes punishable by death, reclusion perpetua, or reclusion temporal prescribe in 20 years.
Crimes punishable by other afflictive penalties prescribe in 15 years.
Crimes punishable by a correctional penalty prescribe in 10 years.
The crime of libel or other similar means prescribes in 1 year.
Oral defamation and slander by deed prescribe in 6 months.
Light offenses prescribe in 2 months.

Since Acts of Lasciviousness carries a correctional penalty, the State has ten (10) years to institute the case.

3. When Does the Period Start?

According to Article 91 of the RPC, the period of prescription commences to run:

From the day on which the crime is discovered by the offended party, the authorities, or their agents.
If the crime is not discovered immediately, from the time of its commission.

In most cases of Acts of Lasciviousness, the "discovery" coincides with the "commission" because the victim is aware of the act the moment it happens. However, in cases involving minors or victims who were unconscious or under duress, legal arguments regarding the "discovery" point may vary.

4. Tolling or Interruption of the Period

The running of the 10-year prescriptive period is interrupted (paused) when:

A complaint or information is filed in court.
A complaint is filed with the Office of the Prosecutor (for the purpose of preliminary investigation).

The period begins to run again if the proceedings are terminated without the accused being convicted or acquitted, or if the proceedings are unjustifiably stopped through no fault of the victim.

Note on Special Laws: If the act of lasciviousness qualifies as Child Abuse under Republic Act No. 7610, the prescriptive period and its commencement may differ. Under Republic Act No. 11596 and related jurisprudence concerning minors, the prescriptive period for certain sexual offenses against children only begins to run from the time the victim reaches the age of majority (18 years old), ensuring that the delay caused by the vulnerability of childhood does not bar justice.

5. Jurisprudential Distinctions

It is vital to distinguish Acts of Lasciviousness (Article 336) from Slander by Deed (Article 359).

Acts of Lasciviousness: The offender acts with lewd design (sexual intent). Prescription: 10 years.
Slander by Deed: The offender acts to humiliate or cast dishonor upon the victim without lewd design (e.g., slapping a person in public or stripping them to shame them). Prescription: 6 months.

If a case is filed as Acts of Lasciviousness but the court finds the intent was merely to humiliate (Slander by Deed), and more than six months have passed since the incident, the case may be dismissed because the shorter prescriptive period has already lapsed.

Summary Table

Legal Basis	Penalty	Prescriptive Period
Article 336, RPC	Prision Correccional	10 Years
RA 7610 (Child Abuse)	Varies (Higher)	10 to 15 Years (Tolling starts at age 18)