A former senator has expressed that while the Constitution does not mandate that a senator be a lawyer to preside over an impeachment trial, a senator with a legal background would be "better equipped" for the role.

In a television interview, former Senate President Franklin Drilon disclosed that there is an advantage for a senator with legal background to lead an impeachment court.

"Certainly it is an advantage, but being a non-lawyer will not disqualify you from presiding over the impeachment court because that is an obligation and a duty imposed by the Constitution regardless of your profession," said Drilon.

He added that a lawyer would likely be "better equipped to rule immediately on any issue on the floor."

However, he clarified that a non-lawyer presiding officer could still seek time to consider rulings.

"You can always ask, I will rule this later in the day or next week or tomorrow. There is nothing that would prevent you from doing that," Drilon said.

Drilon is one of only seven individuals who served as senator-judges in the impeachment trials of both former President Joseph Estrada and former Chief Justice Renato Corona.

The other six are the late Senator Miriam Defensor-Santiago, former Senate President and now Chief Presidential Legal Counsel Juan Ponce Enrile, former Senator Gringo Honasan, Senator Loren Legarda, former Senator Serge Osmeña, and incoming Senator Vicente Sotto III.

Under the 1987 Constitution, the Senate President presides over impeachment courts, except in cases involving the President, where the Chief Justice of the Supreme Court takes on the role.

Chief Justice Hilario Davide Jr. presided over Estrada's impeachment in 2000, while Senate President Juan Ponce Enrile, a lawyer, presided over Corona's impeachment in 2012.

Three lawmakers are expected to vie for the Senate presidency -- incumbent Senate President Chiz Escudero, returning Senator Imee Marcos, and Sotto.

Of the three potential contenders, only Escudero, a graduate of the University of the Philippines College of Law who passed the bar in 1994, is a lawyer.