Short answer. Possibly, but not automatically. Under Article 11(1) of the Revised Penal Code, hurting someone who attacked you first is justified self-defense only if three things concur: unlawful aggression by the other person, reasonable necessity of the means you used, and lack of sufficient provocation on your part.
What the law says
do not incur any criminal liability
Revised Penal Code, Article 11 — Justifying Circumstances: Self-Defence And Defence Of Others. Read the full provision →
What the law says
Anyone who acts in defense of his person or rights
Revised Penal Code, Article 11 — Justifying Circumstances: Self-Defence And Defence Of Others. Read the full provision →
What the law says
Unlawful aggression
Revised Penal Code, Article 11 — Justifying Circumstances: Self-Defence And Defence Of Others. Read the full provision →
What the law says
Reasonable necessity of the means employed to prevent or repel it
Revised Penal Code, Article 11 — Justifying Circumstances: Self-Defence And Defence Of Others. Read the full provision →
What the law says
Lack of sufficient provocation on the part of the person defending himself
Revised Penal Code, Article 11 — Justifying Circumstances: Self-Defence And Defence Of Others. Read the full provision →
Self-defense is a justifying circumstance
Article 11 lists justifying circumstances — cases where a person do not incur any criminal liability. The first is self-defense: Anyone who acts in defense of his person or rights, provided the required circumstances concur. If your self-defense is complete, you commit no crime at all — the law regards your act as lawful, not merely excused. But the fact that the other person attacked first does not, by itself, settle the matter. Self-defense is proved by its three requisites, and all of them must be present for the justification to hold.
The three requisites
The article requires that three circumstances concur. First, Unlawful aggression — a real, imminent, unlawful attack on you; this is the indispensable element. Second, Reasonable necessity of the means employed to prevent or repel it — your response must be reasonably proportionate to the danger, not excessive. Third, Lack of sufficient provocation on the part of the person defending himself — you must not have sufficiently provoked the attack yourself. That someone hit you first usually supplies the aggression, but the other two requisites still have to be met before the law will treat your response as justified self-defense.
Unlawful aggression must still exist when you act
Timing matters. The aggression must be actual or imminent at the moment you defend yourself. If the attack has already ceased — the aggressor has fled, been disarmed, or clearly stopped — striking back afterward is no longer defense but retaliation, and the justification fails. "He attacked me first" is not a free pass to respond at any later time or to any degree. The law protects the person meeting an ongoing or imminent unlawful attack with a proportionate response, not one who answers a finished assault with fresh violence of his own.
Proving it, and what happens if it is incomplete
Because self-defense admits the act but claims it was justified, the accused generally bears the burden of proving its elements clearly. If all three requisites are present, there is no criminal liability. If unlawful aggression is present but one of the other requisites is missing — say the means were excessive — the defense may be incomplete, which does not fully absolve but can reduce the penalty as a mitigating circumstance. What it cannot do is turn a completed act of retaliation, with no ongoing aggression, into lawful self-defense.