June 20, 2025
Introduction
Self-defence is a long-standing defence in criminal law, grounded in the recognition that the law does not require a
person to submit to unlawful force. It operates not as a plea of mercy but as a
justification that, when properly invoked, exonerates an accused from criminal
liability. Yet this defence is carefully delimited by the interrelated
principles of necessity, proportionality, and reasonableness, each ensuring
that the use of force remains a measure of protection rather than retaliation.
In Zambia, the doctrine is codified under Section 17 of the Penal Code,[1] and has been the subject of extensive judicial exposition, most notably in People v Phiri and Another.[2] Drawing on both domestic jurisprudence and comparative common law, this article explores how Zambian courts have circumscribed the ambit of self-defence within these guiding principles.
The Statutory Foundation: Section 17 of the Penal Code
Section 17 of the Penal Code
provides that:
“Subject to any other provisions of this Code or another law for the time being in force, a person shall not be criminally responsible for the use of force in repelling an unlawful attack upon his person or property; or the person or property of any other person if the means he uses and the degree of force he employs in doing so are no more than is necessary in the circumstances to repel the unlawful attack.”
This provision encapsulates the
necessity and proportionality requirements, limiting the defensive force to
what is “no more than… necessary” in the circumstances. The statutory
formulation reflects long-standing common law principles articulated in Palmer
v R,[3] where Lord Morris observed
that “a man who is attacked may defend himself... but may only do what is
reasonably necessary.”
Justice Dr Patrick Matibini SC, in the People v Phiri, confirmed that self-defence under section 17 is “a matter of justification and not merely a matter of mercy to a defender,” emphasising that it operates as a complete defence if properly established.
Principles of Self Defence
1. The Principle of Necessity
The first limit of lawful
self-defence is necessity, the requirement that force be used only where
unavoidable to avert an imminent unlawful attack. The doctrine presupposes
immediacy and compulsion: the defender must face a threat that leaves no
reasonable alternative but to use force.
In Phiri, counsel argued that the
first accused struck the deceased with a hammer to protect himself after being
attacked. The High Court, however, held that the defence failed because the
accused had engineered the confrontation by luring the deceased into his home;
his act was therefore not the reaction of one under imminent peril but of one
acting with deliberation. The court drew on authorities such as The People
v Lewis,[4] and Mwale v R,[5] where the courts
recognised that a person under a sudden attack “acts under the stress of the moment” and cannot be expected to
display perfect judgment.
Nonetheless, once the danger has
passed, the continued use of force ceases to be necessary. As stated in Palmer
v R, “if the attack is over
and no sort of peril remains, the employment of force may be by way of paying
off an old score.” Thus, necessity confines defensive action to the
duration of the threat.
2. Proportionality and the Calibration of Force
The second element,
proportionality, requires that the degree of force used correspond to the
gravity of the threat. Even where the need to act is established, excessive or
disproportionate violence will defeat the defence. In Mancini v Director of Public
Prosecutions,[6] the use of a dagger in
response to a fist-fight was held disproportionate. Zambian jurisprudence
follows the same principle. In Tembo v The People,[7]
the Supreme Court observed that although the defence of self-defence is
absolute, “if the force used was
unreasonable, the proper verdict is murder.”
This was reaffirmed in the case of the People v Phiri and another, wherein it was held that by
repeatedly striking an unarmed man on the head with a hammer far exceeded what
was necessary to repel any threat. The decision underscores that section 17
requires not only a defensive purpose but also a measured response, consistent
with community standards of moderation and restraint.
3. Reasonableness: The Objective Standard
The third principle,
reasonableness, invokes the objective test by which necessity and
proportionality are judged. The question is whether a reasonable person in the
accused’s position would have considered such force necessary and proportionate
to avert the danger.
English decisions such as R
v Owino,[8]
and R v Gladstone Williams,[9]
have clarified that the assessment combines subjective and objective elements:
the accused must honestly believe that force is necessary, but the force used
must also be objectively reasonable in light of that belief.
Zambian courts have adopted a
similar approach. In the Phiri case,
the High Court held that the accused’s conduct was neither instinctive nor
defensive; it was calculated and deliberate, lacking the spontaneous element
characteristic of genuine self-defence. Reasonableness, therefore, acts as the
doctrinal safeguard against pretextual or revengeful violence.
Excessive Force and the Distinction Between Murder and Manslaughter
Where the accused acts under an
honest belief in the need for defence but employs excessive force, Zambian law
distinguishes between unlawful retaliation (murder) and mistaken or excessive
defence (manslaughter). In Mulenga v The People,[10] the Court of Appeal held
that an honest though mistaken use of excessive force, while unjustifiable,
negated
malice aforethought and reduced the offence to manslaughter.
This nuanced approach preserves
the balance between accountability and human frailty. It recognises that one
defending against an attack cannot “weigh to a nicety” the precise measure of
his response (Palmer v R), yet
insists that any gross disparity between attack and retaliation evidences
intent to take “violent and murderous revenge.”
Conclusion
Self-defence under section 17 of the Zambian Penal Code represents a lawful justification constrained by
necessity, proportionality, and reasonableness. These principles together
ensure that the defence protects human life without licensing excessive
violence.
The High Court’s reasoning in the People
v Phiri and Another reaffirms that lawful defence must arise from immediate
peril, employ no more force than necessary, and remain consistent with what a
reasonable person would deem justified. In maintaining this equilibrium,
Zambian law preserves both the individual’s right to self-protection and the
collective imperative of public order, the twin pillars upon which the
legitimacy of criminal justice rests.
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