Foreign Secretary Perfecto Yasay Jr. could be charged with perjury if proven that he lied about his citizenship, Senator Panfilo Lacson said on Monday.

During his confirmation hearing at the Commission on Appointment’s committee on foreign affairs, Yasay insisted that he never became an American citizen.

READ: Yasay admits naturalization try, but insists he isn’t US citizen

But the Philippine Daily Inquirer reported that based on documents, Yasay acquired US citizenship and took his oath as an American citizen in 1986. He only renounced his US citizenship at the US Embassy in Manila on June 28, 2016, or just two days before President Rodrigo Duterte appointed him to the Cabinet.

“That could be a cause for a complaint for perjury. If it can be proven na nag-lie siya at authentic ang mga dokumento (that he lied and that the documents were authentic),” Lacson, who presided over Yasay’s confirmation hearing, told reporters when sought for comment.

“Remember kailangan i-authenticate natin ang mga document at ipakita na kontra yan sa kanyang testimony under oath. In-administer natin ang oath sa kanya,” he said.

(Remember, we have to authenticate the documents and show that it was contrary to his testimony under oath. We administered his oath)

Asked if lying under oath could be used by the Commission to reject Yasay’s confirmation, Lacson said: “That should be the least of his worries.”

“Pag may perjury, kasi may criminal offense. Kaya huwag siya mag-worry masyado kung di siya ma-confirm. Mas ang problema niya ang pwede niyang kaharapin na kaso,” he said.

“(Perjury is a criminal offense. So he should not worry too much if he is not confirmed. The bigger problem is the possible case that he would face)

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