"I’ve been president and being president, you have information that others do not have. They help you make a decision but you cannot share all the information with others," she added.
Arroyo urged the public to just trust the President, after all, he is still the President of the country, he knows what he is doing.
"So therefore, it is important that we just trust the president because he knows what we don't know and he knows what he's doing. So let us all support the martial law in Mindanao," she said.
She recalled the time when she became a president. During that time, she said, Mindanao was very complicated. Despite the peace agreement in 1996, the Moro National Liberation Front (MNLF) continued their rebellion agaisnt the government.
"By time I became president, I inherited a battleground in Mindanao. The rebellion gave ground led by the [Moro National Liberation Front (MNLF)] in 1972. And when there was a peace agreement in 1996 the MILF continued the rebellion... and when I became president it became complicated because of the ascendants of international terrorism and religious warfare in 1997," she said.
The former Philippine President declared martial law in Maguindanao after the Ampatuan massacre on November 23, 2009, killing 58 people.
The the writ of habeas corpus in the province except in some areas. This was the first declaration since 1972.
"We are confident that this one is covered by the Constitution," Ermita assured.
"The condition of peace and order in the province of Maguindanao has deteriorated to the extent that local judicial systems and other government mechanisms are not functioning and thus endangering public safety," said Ermita at a press briefing at the Palace.
Press Secretary Cerge Remonde pointed out that the judicial process in the province is being hampered as "no judges will take the case, no judges will pursue the proper search warrants, or warrant of arrests."
Reports states that Arroyo declared martial law, however, when the media contacted Remonde, she denied the rumors while the then Presidential Adviser for Mindanao Affairs Jesus Dureza said he had no information on the matter.
President Duterte's martial was supported by 17 senators and six among them voted against it when Arroyo imposed the military rule in Maguindanao.
They were Senators Francis Escudero, Richard Gordon, Gregorio Honasan II, Panfilo Lacson, Loren Legarda, and Juan Miguel Zubiri.