President Duterte's declaration marks the second localized declaration of martial law in the country and the third time the country or a portion thereof has been subjected to martial rule.

On paper, sufficient safeguards have been put in place to avoid a repeat of the horrors of martial law in the 70s.

Under the Constitution, the President may only declare martial law in cases of invasion or rebellion when the public safety requires it. The effectivity of the declaration can only last for 60 days.

The Constitution also states: "Within forty-eight hours from the proclamation of martial law or the suspension of the privilege of the writ of habeas corpus, the President shall submit a report in person or in writing to the Congress."

"The Congress, voting jointly, by a vote of at least a majority of all its Members in regular or special session, may revoke such proclamation or suspension, which revocation shall not be set aside by the President."

"Upon the initiative of the President, the Congress may, in the same manner, extend such proclamation or suspension for a period to be determined by the Congress, if the invasion or rebellion shall persist and public safety requires it."

The Supreme Court may also review, in an appropriate proceeding filed by any citizen, the sufficiency of the factual basis of the proclamation of martial law or the suspension of the privilege of the writ or the extension thereof, and must promulgate its decision thereon within 30 days from its filing.

A state of martial law does not suspend the operation of the Constitution, nor supplant the functioning of the civil courts or legislative assemblies, nor authorize the conferment of jurisdiction on military courts and agencies over civilians where civil courts are able to function, nor automatically suspend the privilege of the writ.

Prof. Ed Garcia, one of the framers of the 1987 Constitution, said the safeguards were put in place to ensure that there is no arbitrary declaration of martial law.

"Martial law provisions were drafted to ensure that there can be no arbitrary declaration of martial law. Measures were put in place to prevent recurrence of martial rule not fully justifiable or justified. Moreover, martial law has been made time bound subject to extension only if legislators deem situation warrants it."

ANC, May 24, 2017