Politics in the Philippines are governed by a three-branch system of government. The country is a democracy, with a president who is directly elected by the people and serves as both the head of state and the head of government. The president serves as the leader of the executive branch and is a powerful political figure. A president may only hold office for one six-year term. The bicameral Congress consists of two separate bodies: the Senate, with members elected at-large across the country, and the larger House of Representatives, with members chosen mostly from specific geographic districts. The Congress performs legislative functions. The judiciary is overseen by the Supreme Court of the Philippines and has extensive review jurisdiction over judgments issued by other governmental and administrative institutions.

The legal system, which covers both civil and criminal law, has been impacted by the prior rule of both Spain and the United States. Spanish control was mostly supported by local intermediaries, which resulted in an elite-dominated system. The United States took sovereignty of the whole archipelago following the Spanish–American war, suppressing the nascent First Philippine Republic that had been declared after the end of Spanish administration. Control by the United States resulted in democracy and institutions that were fashioned after the American political system. Martial law's implementation hampered this. National politics were ruled by a two-party system when the country attained independence in 1946 and changes brought about by the restoration of democracy are what led to the multi-party system that exists today. There have been various levels of left-wing insurgencies since independence, as well as a continuous Islamic insurgency.

Elections are held every three years, although the president, vice-president, and Senators are elected for six-year terms. Results are determined through plurality voting, including plurality-at-large for elections (such as for the Senate) with multiple winners. A mixed-member proportional representation system is used to elect a minority of the House of Representatives. Local government units have some revenue-generating powers, under a code intended to decentralize power away from the national government. Administrative structures at local levels are designed to foster civil society participation.

Politics is dominated by a powerful elite, with dynastic politics common at both the local and national levels. Political parties are weak, with elections instead dominated by individual and familial personalities. Political positions provide extensive opportunities for patronage, and clientelism and electoral fraud are common. Corruption is considered widespread, while state institutions are relatively weak. Politics has been heavily influenced at times by the Catholic Church, the Philippine military, and the United States. Despite pessimism about the potential for political change, democracy maintains strong public support, and voter turnout is high.

Executive

Executive power is vested to the president, who is both head of state and head of government. This individual is directly elected to a six-year term through a single-round first past the post election, and being limited to one term are unable to seek re-election. To be eligible for the presidency, an individual must be at least 40 years old, and must have resided in the Philippines for the decade prior to the election. Presidents may legislate through executive orders and other administrative actions, and must approve or veto bills coming from the Congress.

The vice president, limited to two consecutive six-year terms, is elected separately from the president. This means the president and vice president may be from different political parties. While the vice president has no constitutional powers aside from acting as president when the latter is unable to do so, the president may give the former a cabinet office. In case of death, resignation, or incapacitation, of the president, the vice president becomes the president until the expiration of the term. The vice president may also serve as Acting President if the president is temporarily incapacitated. Following in the line of succession are the Senate president and the Speaker of the House.

Executive power is exercised through the Cabinet, who are appointed by the president. While the appointees may wield executive power, all powers and responsibilities ultimately remain with the president, who may overrule any decision made by a cabinet member. The Cabinet includes the heads of executive departments. Actions taken by executive and administrative officials are taken as actions exercised by the president. Cabinet members may not be members of Congress. Close relatives of the president are explicitly barred from certain offices.

The president is also the commander in chief of the Armed Forces of the Philippines, thereby ensuring civilian supremacy over the military. This title gives the president several emergency military powers, such as the ability to suspend habeas corpus and declare martial law, although these powers automatically end after 60 days unless extended by Congress, and can be reviewed by the Supreme Court. The president also proposes a national budget, which Congress may alter before they adopt it.

The president wields significant political power, including considerable influence over supposedly independent agencies due to the power of appointment. The president directly controlled the Philippine Development Assistance Fund until the Supreme Court declared this unconstitutional in 2013. Following this, the Disbursement Acceleration Program was created to allow the president to direct funds, although some parts of this new program have similarly been declared unconstitutional. Such influence means that the legislature has never overcome a presidential veto, despite having the theoretical power to do so. A commission on appointments, independent from the legislature but made up of members from it, has the power to veto presidential appointments. However, court rulings mean the president can renominate an individual repeatedly upon rejection, and that that individual can effectively carry out the role by being officially in an acting capacity. The strength of the presidency combined with weak state institutions exacerbates corruption in the country.

Under the 1987 constitution, the House of Representatives has the power to impeach the president through a vote of one-third of its members, and the Senate decides upon the case. Impeachment proceedings against an individual can not occur more than once per year, which can be abused through the filing cases with weak impeachment claims to forestall the filing of stronger cases. President Joseph Estrada was the first Asian head of state to be tried following impeachment, although he was not ousted by the Senate. No president has ever been ousted through impeachment.

Legislature

Congress is a bicameral legislature. The upper house, the Senate, is composed of 24 senators. These are elected through plurality-at-large voting, with the entire country considered a single district. The senators elect amongst themselves a Senate President. Half of the Senate seats are contested every three years, and senators are limited to serving a maximum of two consecutive six-year terms.

The lower house is the House of Representatives, currently composed of 311 representatives, with 20% elected via party-list system, and the rest elected from legislative districts. Legislative districts are intended to be roughly equal in population, and every city with a population of at least 250,000 people is guaranteed at least one representative. The House of Representatives is headed by the Speaker. Representatives are elected every three years, and are limited to three three-year terms.

Each bill needs the consent of both houses to be submitted to the president for his signature. If the president vetoes the bill, Congress can override the veto with a two-thirds supermajority. If either house voted down on a bill or fails to act on it after an adjournment sine die, the bill is lost and would have to be proposed to the next congress, with the process starting all over again. Congress's decisions are mostly via majority vote, except for voting on constitutional amendments and other matters. Each house has its inherent power, with the Senate given the power to vote on treaties, while money bills may only be introduced by the House of Representatives. The constitution provides Congress with impeachment powers, with the House of Representatives having the power to impeach, and the Senate having the power to try the impeached official.

The control the legislature has over funding includes individual discretionary funds. These funds are considered an avenue for patronage politics and are often seen a symbol of corruption. They are derogatorily referred to as "pork barrel" funds. In addition to being able to use such funds to curry favor or gain support, politicians can personally benefit from kickbacks, which are often directly used for re-election campaigns. The Priority Development Assistance Fund scam highlighted the link between such funding and legislative support for executive initiatives.

, the PDP-LABAN, the Nacionalista Party (NP), the Nationalist People's Coalition (NPC), National Unity Party (NUP), and the Liberal Party (LP) are the parties with largest membership in Congress. The party of the sitting president controls the House of Representatives, where members often change party affiliation to join the president's party. The Senate has generally acted more independently.

Judiciary

The judiciary is headed by the Supreme Court, which lies at the top of three lower court levels. The Supreme Court is the court of last resort, and can decide on the constitutionality of laws. Vested with the responsibility of overseeing the other branches of government, the Supreme Court has significant powers, able to go as far as overruling discretionary decisions made by political and administrative individuals and bodies, giving it powers usually seen as those of the executive and legislature. The court can effectively create law without precedent, and such decisions are not subject to review by other bodies.

All lower levels of courts have their bases through legislation, rather than the constitution. Their proceedings are determined by the Supreme Court. Courts are arranged in a three-level hierarchy, with each level able to review only rulings at lower levels. Within the regular court system, the Court of Appeals is the second-highest appellate court. Below this, Regional Trial Courts have original jurisdiction on most criminal matters, and are the main trial courts. The Regional Trial Courts are organized within judicial regions, which correspond to the administrative regions. The lowest level courts are the Metropolitan Trial Courts.

Alongside the regular courts, a variety of special courts have been set up at various levels of the judicial system. The Court of Tax Appeals was set up specifically to rule on tax matters. The Sandiganbayan is a special court set up to deal with cases of government corruption. Some Regional Trial Courts specialize in a particular sort of case, such as heinous crime courts, family courts, and environmental courts. Sharia courts, which have been set up in some regions on the same level as Regional and Metropolitan courts, rule on personal law where both parties are Muslim. Some administrative bodies are able to exercise very specific quasi-judicial powers, as determined by law.