Two years after Pelaez was decided, the issue again came to fore in Municipality of San Joaquin v. Siva. The Municipality of Lawigan was created by virtue of Executive Order No. 436 in 1961. Lawigan was not one of the municipalities ordered annulled in Pelaez. A petition for prohibition was filed contesting the legality of the executive order, again on the ground that Section 68 of the Revised Administrative Code was unconstitutional. The trial court dismissed the petition, but the Supreme Court reversed the ruling and entered a new decision declaring Executive Order No. 436 void ab initio. The Court reasoned without elaboration that the issue had already been squarely taken up and settled in Pelaez which agreed with the argument posed by the challengers to Lawigans validity.
In the 1969 case of Municipality of Malabang v. Benito, what was challenged is the validity of the constitution of the Municipality of Balabagan in Lanao del Sur, also created by an executive order, and which, similar to Lawigan, was not one of the municipalities annulled in Pelaez. This time, the officials of Balabagan invoked de facto status as a municipal corporation in order to dissuade the Court from nullifying action. They alleged that its status as a de facto corporation cannot be collaterally attacked but should be inquired into directly in an action for quo warranto at the instance of the State, and not by a private individual as it was in that case. In response, the Court conceded that an inquiry into the legal existence of a municipality is reserved to the State in a proceeding for quo warranto, but only if the municipal corporation is a de facto corporation.
(Source: SC Website, Case law)