Under the 1987 Constitution, the Congress cannot even invite the President to appear before it to give testimony, with the sole exception being the Question Hour under Article VI, sec. 22 (relating to appearance by Department Heads, with the consent of the President). The only appearance that the President makes before Congress is the State of the Nation Address or any other occasion when he chooses to address a Joint Session of Congress, with advice to and the consent of both Houses.
More than the legalities, however, the President should not be subjected to such questioning.
This ad hoc procedure (it is not found in any statute or constitutional norm) demeans and belittles the Office of the President. Moreover, it exposes the Office to the possibility that the President may be made to "testify" outside of an impeachment trial or to "give statements" outside of policy which may lead to impeachment motions. Finally, it serves no useful purpose because it is neither "in aid of legislation" or towards a determination of probable cause or for purposes of impeachment.
The President's daily "tick tock" is something that he may choose to disclose or keep confidential. Should he be called--and should he choose to--"testify" before the De Lima panel, the President should now consider his daily activities "fair game" for any sort of inquiry.
More than this, however, there is no need for the President himself to "give his side" because these are either matters of "judicial notice" or public record. Everyone in the Executive Branch is considered his alter egos if they are acting within their official functions, including the Justice Secretary who is the one contemplating the "testimony" of the President. They should be the ones "testifying", not the President.
The First President Aquino made a crucial mistake which "demeaned" her Presidency when she sued two journalists for libel. The Second President Aquino would make a crucial mistake which would belittle his Presidency if he does not shoot this ill-conceived idea down before it sprouts wings.
Unsolicited advise to the Second President Aquino so that we can close this episode, place accountability squarely where it should be and move forward:
1. Remove every perception or hint that there could even be a whitewash by:
1.1. Dissolving the fact-finding panel led by Justice Secretary De Lima; and
1.2. Instead, inviting Congress to convene a Joint Committee to investigate this incident once and for all, with a definite and limited timeline and with a clear commitment to not invoke "Executive Privilege."
1.3. Placing all relevant heads of agencies and persons concerned at the Joint Committee's disposal.
2. Personally, ask for the most pugnacious, most hostile, most adversarial members of Congress to co-chair the Joint Committee (e.g., Joker Arroyo for the Senate and Edcel Lagman/Gloria Macapagal-Arroyo for the House).
3. Make it clear, however, to the Joint Committee that you expect an objective, impartial, sober and quick resolution to this issue through a clear, detailed, objective Report.
4. Take action on the Report as you see fit.
Fans of The West Wing may remember a similar tack taken by the fictitious Bartlet administration in that television show when the fictitious President Bartlet was caught not disclosing a debilitating illness to the public. Sometimes, fiction is stranger than truth and, in this case, more compelling, instructive and relevant.