Requirements of valid custom under the law of jurisprudence

Salmond observes 'CUSTOM is to society what law is to the State'. 

A custom may be legal or conventional. Legal Custom has the force of the law is conventional in usage.

The following are the requirements of a valid custom -

1. Immemorial Antiquity: The local custom should be long-standing or of a fixed period that can be determined. Immemorial means beyond the memory of any living person. Hence, the custom must have been observed over a period, beyond the memory of any living person, i.e., for over 100 years.
2. Continuity : The custom must have been enjoyed continuously. If no living man can contradict the custom set up, it must be presumed to be valid.
3. Enjoyment as of right: The custom must have been enjoyed as of right. If the custom has only been mentioned or followed by force or by stealth or with the license it can have no claim to stand as a right. It must have been followed openly.
4. Certainty : The custom must be certain, clear, and definite. That which is vague or not impressive will fail.
5. Reasonability: The custom must be reasonable. This is the most complex and difficult of the requirements of a valid custom. What is reasonable or not is to be decided by the court in accordance with the prevailing notions of natural justice and public morality. Custom must not be either immoral or contrary to a public utility.
6. Conformity with the general law: A local custom will not be admitted if it conflicts with the fundamental principles of the law of the land.
7. Conformity with statute law: The local custom must not conflict with any statute or any rule thereunder. '
8. Compatibility with other customs: It must not be incompatible with other customs within the same locality. The court cannot sanction two hostile rules or customs.