In City of Manila v. Laguio, Jr.,18 the Court restates the tests of a valid ordinance thusly:
The tests of a valid ordinance are well established. A long line of decisions has held that for an ordinance to be valid, it must not only be within the corporate powers of the local government unit to enact and must be passed according to the procedure prescribed by law, it must also conform to the following substantive requirements: (1) must not contravene the Constitution or any statute; (2) must not be unfair or oppressive; (3) must not be partial or discriminatory; (4) must not prohibit but may regulate trade; (5) must be general and consistent with public policy; and (6) must not be unreasonable.19
As jurisprudence indicates, the tests are divided into the formal (i.e., whether the ordinance was enacted within the corporate powers of the LGU, and whether it was passed in accordance with the procedure prescribed by law), and the substantive (i.e., involving inherent merit, like the conformity of the ordinance with the limitations under the Constitution and the statutes, as well as with the requirements of fairness and reason, and its consistency with public policy).
http://www.chanrobles.com/cralaw/2013decemberdecisions.php?id=1103
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