Article 3, SECTION 22

----- Ex post facto laws -----

People v. Jabinal

– possession of unlicensed firearms; secret agent; -

No criminal liability would attach to such possession of said firearm in spite of the absence of a license and permit. Jabinal must be absolved; Jabinal may not be punished for an act which at the time it was
done was held not to be punishable; (case of SC abandoning previous decisions; stare decisis)

----- Bill of Attainder -----

People v. Ferrer

– constitutionality of the [then] Anti-Subversion Act – A bill of attainder is a legislative act which inflicts
punishment without a trial; Anti-Subversion act not a bill of attainder; It does not specify the CPP or its members; CPP is used for definition purposes only because in the law, it also says “any other organization having the same purpose and their successors”; mere membership to the CPP not punished; even if the Act specifies individuals, this feature is not enough to consider it a bill of attainder

People v. Sandiganbayan

– violation under Anti-Graft and Corrupt Practices Act
– The new 15-year prescriptive period (formerly 10) in the Act cannot be given retroactive effect because it will be prejudicial to the accused.