The 1987 Philippine Constitution vests the legislative power in a bicameral Congress composed of the Senate and the House of Representatives. While Article VI enumerates a comprehensive list of powers—ranging from law-making, taxation, appropriation, declaration of war, impeachment, concurrence in treaties and amnesties, canvassing of presidential elections, and the calling of a constitutional convention—the Constitution does not contain an explicit “necessary and proper” clause similar to Article I, Section 8 of the United States Constitution. Nevertheless, Philippine constitutional law has long recognized that Congress possesses implied powers that are indispensable to the effective discharge of its express constitutional functions.

These implied powers are not free-floating or discretionary; they are strictly ancillary and derive their legitimacy from the doctrine that the grant of an express power carries with it all incidental powers necessary to make the express power effective. This principle was firmly established even under the 1935 Constitution and has been consistently upheld under the 1987 Constitution.

Historical Development

Under the Malolos Constitution of 1899, the National Assembly was recognized as possessing inherent powers necessary for self-preservation and effective legislation, including the contempt power. The 1935 Constitution did not expressly grant the power of legislative inquiry in aid of legislation, yet the Supreme Court in Arnault v. Nazareno (87 Phil. 29 [1950]) declared that the power of inquiry—with its concomitant contempt power—was an essential and appropriate auxiliary to the legislative function. The Court categorically held:

“The power of inquiry—with process to enforce it—is an essential and appropriate auxiliary to the legislative function… A legislative body cannot legislate wisely or effectively in the absence of information respecting the conditions which the legislation is intended to affect or change.”

The 1973 Constitution for the first time expressly provided for the power of inquiry in aid of legislation (Article VIII, Section 13). The 1987 Constitution retained and strengthened this provision in Article VI, Section 21 while adding the explicit safeguard that the rights of persons appearing in such inquiries shall be respected.

Despite the express grant of the inquiry power in the present Constitution, the ancillary contempt power remains implied rather than express, preserving the Arnault doctrine.

Nature and Scope of Implied Powers

Philippine jurisprudence has consistently applied the following principles:

Implied powers are those that are necessary (not merely convenient) to the exercise of an express power.
The implied power must be directly germane to the express power and must not violate any constitutional prohibition.
Implied powers are subject to the same limitations as express powers, particularly the Bill of Rights and the principle of separation of powers.

The Supreme Court has repeatedly affirmed that Congress is not confined to the powers expressly granted; it may exercise those that are necessarily implied. In Angara v. Electoral Commission (63 Phil. 139 [1936]), the Court recognized the implied power of the Senate Electoral Tribunal to be the sole judge of all contests relating to the election, returns, and qualifications of Senators, even though the tribunal’s composition and authority were constitutionally prescribed.

Specific Implied Powers of Congress

1. Power to Punish for Contempt in Legislative Inquiries

This is the most well-established implied power. Although Article VI, Section 21 expressly grants the power of inquiry in aid of legislation, it is silent on the sanction for refusal to obey summons or answer pertinent questions. The Supreme Court has consistently ruled that the power to punish for contempt is necessarily implied.

Key cases:

Arnault v. Nazareno (87 Phil. 29 [1950]) – Established the doctrine under the 1935 Constitution.
In re Sabio (G.R. No. 174340, October 17, 2006) – Reaffirmed under the 1987 Constitution.
Balag v. Senate Committee on Public Accountability (G.R. No. 234608, July 3, 2018) – Upheld indefinite detention until compliance or adjournment of the session, whichever comes first.
Standard Chartered Bank v. Senate Committee on Banks (G.R. No. 167173, December 27, 2007) – Clarified that the contempt power extends only to refusal to attend or testify, not to the content of the testimony itself if privileged.

Limitations:

The inquiry must be in aid of legislation (Bengzon v. Senate Blue Ribbon Committee, G.R. No. 89914, November 20, 1991).
The contempt power cannot be used for punishment, exposure for exposure’s sake, or law enforcement (which belongs to the executive and judiciary).
Detention lasts only until the witness complies or the legislative session ends.

2. Power to Issue Subpoena and Warrants of Arrest

Directly flowing from the contempt power, Congress and its committees may issue subpoena ad testificandum and subpoena duces tecum, as well as warrants of arrest for witnesses who ignore subpoenas. This authority is exercised through the Senate President or Speaker of the House, or through committee chairmen when duly authorized.

3. Oversight Powers

While “oversight” is not an express constitutional term, the Supreme Court has recognized three distinct oversight functions of Congress, all rooted in express and implied powers:

(a) Scrutiny – primarily through the power of inquiry in aid of legislation (Article VI, Section 21) and question hour (Article VI, Section 22).
(b) Investigation – same constitutional basis as scrutiny, but may extend to oversight of executive implementation of laws.
(c) Supervision – exercised through the Commission on Appointments (Article VI, Section 18) and the congressional canvass of presidential elections.

In Francisco v. House of Representatives (G.R. No. 160261, November 10, 2003) and subsequent cases, the Court acknowledged that legislative oversight is an implied power necessary to ensure executive compliance with legislative policy.

4. Fiscal Autonomy of Congress

The Supreme Court has recognized the fiscal autonomy of Congress as an implied power deriving from the principle of separation of powers and the status of Congress as a co-equal branch.

In Civil Liberties Union v. Executive Secretary (G.R. No. 83896, February 22, 1991) and subsequent jurisprudence, the Court held that the legislative branch enjoys fiscal independence, including the automatic release of its appropriations without need of further legislative enactment.

5. Power to Determine Internal Rules and Procedures Beyond Express Provisions

While Article VI, Section 16(3) expressly grants each House the power to determine its rules of proceedings, the Supreme Court has upheld implied powers to interpret and apply those rules, including the power to suspend or reinterpret rules when necessary for legislative efficiency (Santiago v. Sandiganbayan, G.R. No. 128055, April 18, 2001).

6. Power to Conduct Executive Sessions and Protect Deliberative Process Privilege

Congress may hold executive sessions and withhold publication of certain deliberations when public disclosure would defeat the purpose of the deliberation (Chavez v. PCGG, G.R. No. 130716, December 9, 1998, by analogy).

7. Power to Realign or Augment Items Within Its Own Appropriations

Although Article VI, Section 25(5) expressly grants the Speaker and Senate President authority to augment items within their respective chambers from savings, the broader principle of fiscal autonomy implies that Congress may realign funds within its approved budget without executive interference.

Limitations on Implied Powers

All implied powers are subject to:

The Bill of Rights – no implied power can violate due process, free speech, or protection against self-incrimination.
Separation of Powers – Congress cannot exercise implied powers that intrude into judicial or executive domains (e.g., no implied power to decide actual controversies or enforce laws directly).
Published Rules Requirement – inquiries must follow duly published rules of procedure (Article VI, Section 21).
Legislative Purpose Requirement – implied powers exercised in investigations must bear a rational nexus to a legitimate legislative objective.

Conclusion

The implied powers of the Philippine Congress, though not enumerated, are vital to the effective functioning of the legislative department. The Supreme Court has consistently upheld these powers under the principle that the express grant of authority carries with it, by necessary implication, all powers indispensable to its effective exercise. The contempt power, oversight functions, fiscal autonomy, and ancillary procedural authorities constitute the core of Congress’s implied powers under the 1987 Constitution. These powers, however, remain strictly subordinate to constitutional limitations and the fundamental principle that Congress may not, under the guise of implication, arrogate unto itself powers expressly withheld or belonging to the other branches.