The Revised Penal Code Article 12-The following are exempt f r om criminal liability:

Under the Revised Penal Code Article 12-
The following are exempt f r om criminal liability:

1. An imbecile or an i n s a n e person, u n l e s s the l a t t er has a c t e d during a l u c id interval.

When the imbecile or an insane person has committed an act w h i c h the l aw defines as a felony (delito), the court shall order h i s confinement i n o n e o f t h e h o s p i t a l s or asylums e s t a b l i s h e d for
p e r s o n s thus afflicted, w h i c h he shall not be permitted t o l e a v e without first o b t a i n i n g t h e permission of the same court.

2. A p e r s o n under n i n e years of age.* (now 15 years of age and under)

3. A p e r s o n over n i n e y e a r s of a g e and under fifteen, unless he has a c t e d w i t h discernment, i n
w h i c h case, s u ch minor shall be p r o c e e d e d against i n accordance w i t h the provisions of Article 80 of t h i s Code. (now over 15 years of age and under 18)

4. Any p e r s o n who, w h i l e performing a lawful act with due care, c a u s e s a n injury by m e r e 
a c c i d e n t w i t h o u t fault or i n t e n t i o n of c a u s i n g it.

5. Any p e r s o n who acts under the compulsion of an i r r e s i s t i b l e force.

6. Any p e r s o n w h o a c t s u n d e r t h e impulse o f a n  uncontrollable fear of a n equal or g r e a t e r injury.

7. Any p e r s o n w h o fails t o perform an act required by law, w h e n p r e v e n t e d by some lawful or insuperable cause.

*A child fifteen years of age or under is exempt from criminal liability under Rep. Act No. 9344 (Juvenile Justice and Welfare Act of 2006). When s u c h minor i s adjudged t o b e criminally irresponsible, t h e court, in conformity w i t h t h e provisions o f t h i s a n d the preceding paragraph, shall commit  him t o         t h e care and custody of h i s family w h o shall be charged w i t h h i s surveillance and education;
o t h e r w i s e , he shall be committed t o the care of some i n s t i t u t i o n or p e r s o n m e n t i o n e d
i n s a i d Article 80.**

Source: The Revised Penal Code of the Republic of the Philippines/Juvenile Justice and Welfare Act of 2006.