Papua New Guinea

WE THE PEOPLE OF PAPUA NEW GUINEA-
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- acknowledge the worthy customs and traditional wisdoms of our people which have come down to us from generation to generation
- pledge ourselves to guard and pass on to those who come after us our noble traditions and the Christian principles that are ours now.
… (Preamble)

(1) Every person has the right to freedom of conscience, thought and religion and the practice of his religion and beliefs, including freedom to manifest and propagate his religion and beliefs in such a way as not to interfere with the freedom of others, except to the extent that the exercise of that right is regulated or restricted by a law that complies with Section 38 (general qualifications on qualified rights).
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(5) A reference in this section to religion includes a reference to the traditional religious beliefs and customs of the peoples of Papua New Guinea. (Sec. 45)

(1) In this Constitution or an Organic Law-
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"custom" means the customs and usages of indigenous inhabitants of the country existing in relation to the matter in question at the time when and the place in relation to which the matter arises, regardless of whether or not the custom or usage has existed from time immemorial;
… (Schedule 1.2)

(1) Subject to Subsections (2) and (3), custom is adopted, and shall be applied and enforced, as part of the underlying law.
(2) Subsection (1) does not apply in respect of any custom that is, and to the extent that it is, inconsistent with a Constitutional Law or a statute, or repugnant to the general principles of humanity.
(3) An Act of the Parliament may—
(a) provide for the proof and pleading of custom for any purpose; and
(b) regulate the manner in which, or the purposes for which, custom may be recognized, applied or enforced; and
(c) provide for the resolution of conflicts of custom. (Schedule 2.1)

(1) Subject to this Part, the principles and rules that formed, immediately before Independence Day, the principles and rules of common law and equity in England are adopted, and shall be applied and enforced, as part of the underlying law, except if, and to the extent that-
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(c) in their application to any particular matter they are inconsistent with custom as adopted by Part I. (Schedule 2.2)