MANILA, Philippines — President Duterte has advised his son Davao City Vice Mayor Paolo Duterte to attend the Senate investigation into drug smuggling, but to invoke his right to remain silent once he is questioned by his critic, Sen. Antonio Trillanes IV.

Duterte claimed over the weekend that the Senate inquiry has been “degraded” and has become a tool for harassment.

“For what purpose? For harassment…The problem is the processes of the Senate have been degraded. It seems that it looks cheap now,” the President said.

“So once they send a subpoena, I will tell them, ‘S***. What’s the purpose? To investigate?’ If they summon you, all you have to do is to say, ‘No. We will not answer you. I will not answer you. I will (invoke) the right to remain silent.’ Period.”

“My advice to all? If you are called to the Senate... sign it. if you are cited for contempt, then you go to court. And you will say, ‘I have the right to remain silent. I will go there, but that’s it,’” Duterte added.

Duterte said he was ready to provide assistance to those who would be threatened with contempt.

“Do not be afraid of being cited for contempt in the Senate. That’s nothing. If you are summoned, as help from me as President, I will help you. I will send lawyers. I have to say that I represent the person cited to appear, and my answer to him is, ‘Shut up.’ That’s it,” Duterte said.

“So henceforth, the Senate will get nothing. I said that because they have cheapened the image of the Senate as an oppressor – not all but that’s the way it is. Do not be afraid of being questioned.”

Duterte said he would give the same advice to his son Paolo, whose name has been dragged into the entry of P6.4 billion worth of shabu from China.

“My advice to Pulong? Go there, then once he (Trillanes) questions you, tell him ‘I will not answer you, I’m invoking my right of silence,” the President said, referring to his son by his nickname.

Duterte said his son could not incriminate himself and that since the elections last year, Trillanes had already been hitting them. Days before the 2016 election, Trillanes accused Duterte of not declaring billions in his bank accounts, an accusation that the President called “garbage.”

“So what’s the point in answering you?” the President said, referring to Trillanes.

Last month, Customs broker Mark Taguba told a Senate hearing that a group with alleged ties to Paolo had asked him to pay P5 million so that his shipments could enter without scrutiny.

Taguba claimed a certain “Tita Nanie” had told him that the bribe would go to a Davao group led by the vice mayor.

The broker later apologized to Paolo and his brother-in-law Manases Carpio for mentioning them in the probe and cleared them of involvement in drug smuggling.

Duterte previously vowed to step down if it is proven that any of his children is involved in irregularities.

Duterte mocked Trillanes and asked him to refrain from using other people’s statements to fish evidence.

“So if you want evidence, Mr. Trililing (Trillanes), do not get it from the mouth of other people. Go somewhere else…You are not a lawyer. You do not know that,” he added.

Duterte said Trillanes is famous for fabricating stories and there is such a crime as subornation of perjury.

“Then you ask people to execute an affidavit, which is a lie. Ganun ’yan,” Duterte further said.

The President also has the same advice to his son-in-law, Manases, a lawyer, and who happened to represent cigarette firm Mighty King Corp. – which was why he was seen at the Bureau of Customs.

The President said Manases, who is also the nephew of Ombudsman Conchita Carpio-Morales, could also opt not to answer any questions during the Senate hearing especially from Trillanes.

The President said there are four circumstances wherein one cannot testify against another person and one such area is between lawyer and client.

The other circumstances, Duterte said, are between husband and wife, between doctor and patient as well as between priest and laity in confession.

Duterte said Trillanes has been on a fishing expedition and that is all there is to it.

“If you want to find out something, don’t elicit it from my own mouth. You are foolish. Find out everywhere,” he said.– with Edith Regalado