The Philippines is unusual among developing countries in having a strong, bicameral legislature. The constitution establishes a 24-seat Senate and a House of Representatives with 200 elected representatives and up to 50 more appointed by the president. Senators are chosen at large, and the twenty-four highest vote-winners nationwide are elected. Senators must be native-born Filipinos at least thirty-five years old. The term of office is six years, and senators cannot serve more than two consecutive terms.

House of Representatives members are elected in single-member districts (200 in 1991), reapportioned within three years of each census. Representatives must be native-born Filipinos and at least twenty-five years of age. Their term of office is three years, except that those elected in May 1987 did not have to face the electorate until 1992. They may not serve for more than three consecutive terms. In addition, President Aquino was to be empowered to appoint to the House of Representatives up to twenty-five people from "party lists." This stipulation was intended to provide a kind of proportional representation for small parties unable to win any single-member district seats. However, Congress did not pass the necessary enabling legislation. The president also is allowed to appoint up to twenty-five members from so-called sectoral groups, such as women, labor, farmers, the urban poor, mountain tribes, and other groups not normally well-represented in Congress, "except the religious sector." Making these appointments would have provided an opportunity for Aquino to reward her supporters and influence Congress, but she has left most such positions unfilled. All members of both houses of Congress are required to make a full disclosure of their financial and business interests.

The constitution authorizes Congress to conduct inquiries, to declare war (by a two-thirds vote of both houses in joint session), and to override a presidential veto with a two-thirds vote of both houses. All appropriations bills must originate in the House, but the president is given a line-item veto over them. The Senate ratifies treaties by a two-thirds vote.

The first free congressional elections in nearly two decades were held on May 11, 1987. The pre-martial law Philippine Congress, famous for logrolling and satisfying individual demands, was shut down by Marcos in 1972. The 1973 constitution created a rubber-stamp parliament, or National Assembly, which only began functioning in 1978 and which was timid in confronting Marcos until some opposition members were elected in May 1984. In the 1987 elections, more than 26 million Filipinos, or 83 percent of eligible voters, cast their ballots at 104,000 polling stations. Twenty-three of twenty-four Aquino-endorsed Senate candidates won. The lone senator opposed to Aquino was former Minister of Defense Juan Ponce Enrile, her husband's former jailer and her one-time defender. Enrile was seated as the twenty-fourth and final member of the Senate, after the Supreme Court ordered the Commission on Elections to abandon plans for a recount. The neaba new legislature was formally convened on July 27, 1987. The leader of the Senate is the Senate president, who stands next in the line of succession for the presidency after the country's vice president. Generally, the Senate had a reputation as a prestigious body with a truly national outlook, in contrast to the House of Representatives, which had more parochial concerns.

At least three-quarters of those elected to the House were endorsed by Aquino, but her influence was less than these results might seem to indicate. She never formed her own political party but merely endorsed men and women with various ideologies who, because of their illustrious family names and long political experience, were probably going to win anyway. Out of 200 elected House members, 169 either belonged to or were related to old-line political families. Philippine politics still was the art of assembling a winning coalition of clans.

Congress did not hesitate to challenge the president. For example, in September 1987, less than two months after the new Congress convened, it summoned the presidential executive secretary to testify about the conduct of his office. The following year, Congress also rejected Aquino's proposed administrative code, which would have conferred greater power on the secretary of national defense.

The internal operation of Congress has been slowed by inefficiency and a lack of party discipline. Legislation often has been detained in the forty-three House and thirty-six Senate committees staffed with friends and relatives of members of Congress. Indicative of the public frustration with Congress, in 1991 the National Movement for Free Elections (NAMFREL) and the Makati Business Club formed a group called Congresswatch to monitor the activities of sitting congress members and promote accountability and honesty.

Data as of June 1991