Opposition lawmakers on Wednesday assailed the constitutionality of the martial law extension in Mindanao before the Supreme Court.

Albay Rep. Edcel Lagman led the "Magnificent 7" opposition group in filing GR No. 235935.

The petitioners also asked the Supreme Court to issue a temporary restraining order (TRO) or a writ of preliminary injunction to stop the implementation of the challenged re-extension pending adjudication of their petition.

The other petitioners are Akbayan Rep. Tomasito Villarin, Caloocan City Rep. Edgar Erice, Ifugao Rep. Teddy Baguilat Jr., Magdalo Rep. Gary Alejano and Capiz Rep. Emmanuel Billones. Meanwhile, Northern Samar Rep. Raul Daza was unable to join the petitioners.

Named respondents are Senate President Aquilino Pimentel III, House Speaker Pantaleon Alvarez, Executive Secretary Salvador Medialdea, Defense Secretary Delfin Lorenzana, Budget Secretary Benjamin Diokno, and Armed Forces of the Philippines Chief of Staff General Rey Leonardo Guerrero.

The petitioners cited the following grounds for the nullification of the re-extension:

- There is no actual rebellion in Mindanao to justify the re-extension until the end of 2018
- Senate President Pimentel III and Speaker Alvarez, supported by the supermajority in both Chambers of Congress, unduly constricted the period of deliberation and interpellation on the subject extension so much so that the President's request for extension was approved without basis and with inordinate haste.
- Threats of violence and terrorism by remnants of vanquished terrorist groups do not constitute a constitutional basis for extension of martial law because "imminent danger" has been deleted as a ground for imposing martial law under the 1987 Constitution.
- The re-extension of one full year defies the unequivocal intent and mandate of the Constitution of having a limited duration of martial law and its extension
- The Constitution does not allow a series of extensions or re-extensions of a martial law proclamation, which may lead to "extensions in perpetuity".
- The congressional grant of re-extension has no factual anchorage and is afflicted by grave abuse of discretion.
- The President as Commander-in-Chief has the power to call out the armed forces to prevent and subdue lawlessness by remnants of terrorist groups without extending martial law and the suspension of the writ of habeas corpus in Mindanao.

According to President Rodrigo Duterte and his defense, military, and police advisers, the "remnants" of terrorist groups have been monitored as "recruiting" new fighters and "regrouping" to launch new attacks.

As lead petitioner, Lagman underscored the following:

- "Rebellion" or "invasion" is neither a state of mind or a state of fear. It must be actual, not contingent. It must be real, not contrived.
- "Remnants" of vanquished terrorist groups do not have the capacity to launch a rebellion even as the government is molding them into apparent menacing ogres, instead of preempting them by ordinary military and police operations without the need for extending martial law.
- Martial law cannot be extended in Mindanao simply to subdue residual phantoms.
- The improvident extension of martial law and the suspension of the writ of habeas corpus against remnants of terrorist groups is akin to killing a fly with a sledgehammer.

The petitioners likewise asked the Supreme Court to accord judicial notice to the joint approval by both Houses of the Congress of the re-extension because until now, a copy of the enrolled joint resolution is not available.