MANILA - The second extension of martial law in Mindanao violates limits set by the Constitution, petitioners challenging its legality told the Supreme Court Tuesday.

As the High Court opened oral arguments on the pleas, lawyers representing four petitioners argued on the lack of factual basis of the extension of military rule in Mindanao for another year, citing the absence of actual firefights in southern Philippines.

"A year-long extension is aggravating. It violates the manifest Constitutional intent that the proclamation, suspension, and extension [of martial law] must be short and limited," Albay Rep. Edcel Lagman said in his opening statement.

The High Court on Tuesday began hearing oral arguments on four petitions seeking to invalidate the extension of martial law in Mindanao until the end of the year.

Congress last year approved President Rodrigo Duterte's request to extend anew martial law in Mindanao to quell the threat of terrorism. He was initially granted an extension until Dec. 31 last year.

The President had cited remaining security threats on the island in seeking another extension of martial law despite the end of hostilities between government forces and Islamic State-inspired extremists in Marawi City in October.

The firefights, which erupted in May, had prompted Duterte to declare the initial 60-day martial law in all of Mindanao.

• Congress grants Mindanao martial law extension until December

Former Solicitor General Florin Hilbay, counsel for Rosales, meanwhile insisted that military rule is "confined to the actual locality of war."

"Martial law is the assumption of jurisdiction by the military over the civilian population in a theater of war out of necessity and for the protection of the public," he said.

Solicitor General Jose Calida had earlier defended the government's decision to extend martial law anew, saying there is “an ongoing rebellion in Mindanao.”

DEALING WITH THE NPA THREAT

The petitioners also rejected the government's claim that military rule would help quell the communist insurgency.

• Duterte cites terror threat, NPAs in requesting extended martial law

Former Commission on Elections (Comelec) chairman Christian Monsod and former Bayan Muna Party-list Rep. Neri Colmenares argued that the threat of the New People's Army was not part of the original basis for the declaration of martial law.

"The government has been continuously going after the NPA and armed rebel groups for decades, your honor, without martial law," Colmenares said.

"Why impose military rule when the civilian government continues to function?" he said.

Lagman added that the decades-long insurgency is not a "serious threat" since it lacks the capability to defeat state forces.

"The CPP-NPA's almost 50 years of insurgency doesn’t pose a serious threat to the republic’s sovereignty because it has no popular support or capacity to defeat the government's superior forces," he said.

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Monsod meanwhile argued that the extension may have a "conditioning effect" on the public to accept dictatorial rule.

"To imply that martial law with its extraordinary powers is a benign solution to our problems is a misrepresentation that has a conditioning effect on our people to accept authoritarianism until it’s too late to stop and this should not be allowed to happen," he said in his opening statement.

The government's top lawyer had earlier said that rebel groups such as the NPA continued to pose a threat to public safety as he stressed that the state of rebellion in Mindanao was already affirmed by the High Court when it sustained the President's original declaration of martial law in July.

• Supreme Court affirms Mindanao martial law

“The remnants remain a formidable force to be reckoned with, especially since they have established linkage with other rebel groups. These rebel groups – which include the NPAs – are waging rebellion in Mindanao,” Calida said.

• Solgen defends extended Mindanao martial law

The petitioners are opposing the second extension of martial law in Mindanao wary of expanded powers under military rule, abuses of which the country experienced under the late strongman Ferdinand Marcos' authoritarian regime.