Sen. Imee Marcos and Former President Rodrigo Duterte. Jonathan Cellona and Maria Tan, ABS-CBN News/File

MANILA — A Senate committee will hold an investigation Thursday, March 20, into the arrest of former President Rodrigo Duterte on an International Criminal Court (ICC) warrant for alleged crimes against humanity.

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The probe was ordered by Sen. Imee Marcos, the sister of President Ferdinand Marcos, Jr. and the chairperson of the Senate Committee on Foreign Relations.

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"I am calling for an urgent investigation into the arrest [Duterte], an issue that has deeply divided the nation... It is imperative to establish whether due process was followed," she said in a statement on Monday.

Police, airport, and Foreign Affairs officials will be among those invited in the investigation, she said.

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Duterte was arrested Tuesday last week after the Interpol served the arrest warrant issued by the ICC. He was sent to The Hague, Netherlands on the same day.

President Marcos said the Philippine government cooperated with the Interpol and not with the ICC in delivering Duterte to The Hague.

But his sister said her investigation would determine if domestic laws were violated by the arrest, insisting that "our sovereignty and legal processes must remain paramount."

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"The Senate must address these critical concerns to uphold the country’s jurisdiction and to clarify policies governing our law enforcement agencies and their engagement with international tribunals.

Sen. Marcos earlier said the arrest of Duterte was "unacceptable," and even skipped the campaign sortie of candidates backed by her brother. 

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Malacanang said it would not prevent officials from appearing as resource persons in the Senate investigation.

“If necessary, if the inquiry is in aid of legislation, we will respect the request of Senator Imee,” Malacanang Press Officer Claire Castro said when asked whether the Palace was ready to send representatives to the probe.

She said Sen. Marcos was free to conduct her own probe on the issue, as she reiterated that the arrest was in compliance with the law.

“Hindi pa po namin napag-uusapan iyan pero kung iyan po ang nais ni Senadora, she is free to do that...We just complied with all the requirements, with the law regarding the arrest of former President Duterte,” Castro said in a Palace press briefing.

President Ferdinand Marcos Jr earlier said authorities “followed every single necessary procedure” in Duterte’s arrest.

“So, I’m confident that…in further examination, you will find that it is proper and correct,” Marcos Jr said in a Palace briefing last week.

Castro denied the claims of Sen. Bato Dela Rosa that the arrest warrant served to Duterte was illegal.

Dela Rosa, a former national police chief who had enforced the war on drugs, gave an emotional speech before Duterte supporters at the Liwasang Bonifacio in Manila on Saturday where he questioned the former President’s arrest.

"Lahat ng ginagawa nila ay iligal. Kasi 'yung warrant of arrest na kanilang sineserve sa atin, hindi 'yan nanggagaling sa competent authority. Hindi 'yan nanggagaling sa local natin. Hindi 'yan na-recognize natin dahil hindi tayo under sa kanila. Kaya dapat magkaisa tayo," Dela Rosa said. 

Castro responded: “Hindi ba competent authority ang ICC sa paningin po ni Senator Bato?”

The Malacanang official also noted Dela Rosa’s absence during the rally of Duterte supporters in Hong Kong, which she surmised was due to information that the ICC has already issued a warrant against the former Chief Executive.

“Sabi ko nga po, iyan ay normal na manggagaling kay Senator Bato, dahil isa siya sa maaaring ma-consider na co-perpetrator, may takot on his part? Maybe, I cannot answer for him. Pero, tandaan po natin, sa aking pagkakaalam, kung hindi ako nagkakamali, may narinig na din daw po siya na magkakaroon ng warrant of arrest, kaya hindi po siya yata napunta sa HongKong,” she said.

“Hindi po ba, kung talagang alam niya na walang warrant of arrest issued by a competent authority, matapang sinamahan ang dating Pangulong Duterte, and as a matter of fact, dapat nga nauna pa siya kay Senator Robin pumunta sa Netherlands.”

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Meanwhile, Sen. Alan Peter Cayetano, a former foreign affairs secretary of the Duterte administration, stressed the need for fairness and due process in the case of Duterte at the ICC.

“Can you imagine if they issue a warrant tapos bigla na lang you don’t have a remedy of going to court? Biglang 20 generals, 20 lieutenants, 50 colonels, at ilang Secretary ng gobyerno ang biglang dadalhin doon. That’s a possibility,” he said.

The former President is currently detained at the Scheveningen detention center in The Hague.

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