MANILA, Philippines — Filipinos should expect 2018 to be the year when the country's constitutional democracy is replaced with "constitutional authoritarianism" as President Rodrigo Duterte and his allies continue to lay the groundwork for an eventual dictatorship, Sen. Leila De Lima said on Tuesday.

According to the detained senator, Duterte and Congress seemed to be taking the path that the late dictator Ferdinand Marcos treaded when he legitimized his dictatorship in 1972 through a new Constitution.

He said that the president seemed to be bent on keeping his allies and himself in power indefinitely and beyond the present constitutional limits.

"I would like to be optimistic about the new year. But I cannot, since 2018 appears to be the year when our constitutional democracy is replaced with constitutional authoritarianism, a throwback to 1972 when Ferdinand Marcos legitimized dictatorship in the Philippines through a new constitution," De Lima said in another of her handwritten notes from her detention in Camp Crame where she is currently detained on drug-related charges she claimed were trumped up.

De Lima enumerated some of Duterte's actions that she said pointed to his "authoritarian project."

Part of the plan to establish this dictatorial government was the moves to impeach Chief Justice Maria Lourdes Sereno and Ombudsman Conchita Carpio-Morales, according to De Lima, who has been critical of Duterte since he was Davao City mayor.

"The weakening of the independent institutions of our system of checks and balance always precedes the coming of a dictatorship," she said.

Sereno is facing the specter of a full-blown Senate impeachment trial after lawyer Lorenzo Gadon accused her of betrayal of public trust and culpable violation of the Constitution in several of her acts since she became chief magistrate in 2012. The chief justice has denied all the allegations against her.

Morales meanwhile has been threatened with an impeachment case, but none has so far progressed at the House of Representatives.

De Lima said that Mindanao was being experimented on with the extension of martial law until the end of 2018 despite the defeat of Islamic State-inspired Maute group. She said that this could be used as basis for a nationwide martial law despite the absence of invasion or rebellion.

"At the same time, despite martial law and the constitutional authoritarianism project, revolutionary government continues to be floated as an option, and an open invitation remains for the military to support Duterte as the absolute power in this so-called revolution," De Lima said, weeks after the Senate and the House, dominated by Duterte allies, approved the government's request for a one-year extension of martial law in Mindanao.

The president has said that a nationwide martial law is "on the table" if the survival of the republic was already at stake.

The opposition senator also slammed Duterte for his attack on the remaining free and critical press in the country and his supporters' propaganda "laced with fake news and political poison" on social media.

She also blasted Duterte's appointment of former Customs chief Nicanor Faeldon to the Office of Civil Defense, Sandra Cam to the Philippine Charities Sweepstakes Office and other individuals to key government posts despite being implicated in irregularities.

"All these indicate the regime’s bravura that it will never be held accountable because it intends to be in power forever. To assure this, Duterte and his lackeys are preparing to replace our democratic system with an authoritarian one" De Lima said.

READ: Trillanes: Faeldon a 'sacred cow' because he knows Duterte family's 'dark secrets'

She also called on Filipinos to act and prevent this plan from happening.

"Let us all move and act to make this year a happy new year, and a sad year for the forces of evil that still rule over our land," she said.

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