What Is the Presumption of Innocence in PNG?

The presumption of innocence is the best-known principle in criminal law and the most often misunderstood in practice. In Papua New Guinea it is a constitutional guarantee, in section 37(4)(a) of the Constitution.

What it actually means

• The prosecution must prove the case. The accused proves nothing.
• The standard is proof beyond reasonable doubt. If the court is left in reasonable doubt, the verdict is not guilty.
• Silence is not evidence of guilt. Section 37(10) provides that no person shall be compelled in the trial of an offence to be a witness against himself.
• “Not guilty” does not mean “innocent as a matter of fact”. It means the prosecution did not discharge its burden — which is exactly what the presumption requires.

It applies from the charge, not the verdict

The words are “a person charged with an offence”. The presumption operates throughout the proceedings, which has consequences well before trial:

• Bail. Section 42(6) entitles a person arrested or detained for an offence other than treason or wilful murder to bail at all times from arrest to acquittal or conviction unless the interests of justice otherwise require. Detaining an unconvicted person is the exception, and it must be justified.
• Treatment in custody. Section 37(18) requires accused persons to be segregated from convicted persons and subject to separate treatment appropriate to their status as unconvicted persons.
• Committal. A committal hearing decides only whether there is sufficient evidence to put the person on trial — not guilt.

The reverse-onus exception

The qualification in section 37(4)(a) is narrow, and each element limits it:

1. It must be imposed by a law — not by practice or by a court’s preference.
2. It attaches to particular facts, not to the offence as a whole. The prosecution still has to prove the elements.
3. Those facts must be peculiarly within the knowledge of the accused — the classic example being whether a person held a licence, permit or authority.

A provision that in substance requires the accused to disprove guilt is not within the exception, however it is drafted.

“Proved guilty according to law”

The final three words carry weight. Guilt must be established through a lawful process — by an independent and impartial court under section 37(3), on evidence lawfully obtained and properly admitted, with the accused able to test the prosecution case under section 37(4)(f). A conviction that follows a process which was not according to law is not a conviction the Constitution recognises, and section 37(15) guarantees review of every conviction and sentence by a higher court or tribunal.

Sentencing and the presumption

The presumption operates until conviction. After conviction, other constitutional constraints take over — in particular section 37(7), which forbids a penalty more severe in degree or description than the maximum that might have been imposed when the offence was committed, and section 41, under which an act done under a valid law is nevertheless unlawful if in the particular case it is harsh or oppressive or disproportionate. Mandatory minimum sentencing has been considered against these provisions: see SCR No 1 of 1984; Re Minimum Penalties Legislation [1984] PGSC 13; [1984] PNGLR 314.