Alegislature (UK:/ˈlɛdʒɪslətʃər/,US:/-sleɪtʃər/)^[1][2] is adeliberative assembly with thelegal authority to makelaws for apolitical entity such as acountry,nation orcity on behalf of the people therein. They are often contrasted with theexecutive andjudicial powers ofgovernment. Legislatures can exist at different levels of government–national, state/provincial/regional, local, even supranational (such as theEuropean Parliament). Countries differ as to what extent they grant deliberative assemblies at the subnational law-making power, as opposed to purely administrative responsibilities.

Laws enacted by legislatures are usually known asprimary legislation. In addition, legislatures may observe and steer governing actions, with authority to amend the budget involved.

The members of a legislature are called legislators. In a democracy, legislators are most commonly popularlyelected, althoughindirect election and appointment by the executive are also used, particularly forbicameral legislatures featuring anupper house.

The name used to refer to a legislative body varies by country.

Common names include:

• Assembly (from Old Frenchasemblee, cf. assemble)
• Congress (from Latincongressum, "having gone together")
• Council (from Latinconcilium, "calling out with, uniting")
• Diet (from Ancient Greekdíaita, "lifestyle, discussion, decision")
• Estates or States (from Old Frenchestat, "condition, state, the state")
• Parliament (from Old Frenchparlement, "talking")

   

By names:

• Chamber of Deputies
• Chamber of Representatives
• House of Assembly
• House of Chiefs
• House of Representatives
• Legislative assembly
• Legislative council
• National Assembly
• Senate

By languages:

• Cortes (from Spanishcortes, "courts")
• Duma (from Russiandúma, "thought")
• Knesset (from Hebrewk'néset, "meeting")
• Majlis (from Arabicmajlis, "sitting room")
• Oireachtas (From Irishairecht/oireacht, "deliberative assembly of freemen")
• Rada (from Polishrada, "'advice, decision")
• Reichstag (from GermanReichstag, "assembly of the empire")
  • Landtag (from GermanLandtag, "assembly of the country")
• Sansad (from Sanskritsaṃsada, "assembly")
• Sejm (from Polishsejm, "take with, assembly")
• Soviet (from Russiansovét, "council")
• Thing (from Proto-Germanic*þingą, "meeting, matter discussed at a meeting")
  • Husting (from Old Norsehúsþing, "house meeting")
• Veche (from Old East Slavicvěče, "council, agreement")

Though the specific roles for each legislature differ by location, they all aim to serve the same purpose of appointing officials to represent their citizens to determine appropriatelegislation for the country.

Among the earliest recognised formal legislatures was theAthenianEcclesia.^[3] In theMiddle Ages, European monarchs would host assemblies of the nobility, which would later develop into predecessors of modern legislatures.^[3] These were often namedthe Estates. The oldest surviving legislature is theIcelandicAlthing, founded in 930 CE.^[4]

Democratic legislatures have six major functions: representation, deliberation, legislation, authorizing expenditure, making governments, and oversight.^[3]

There exist five ways that representation can be achieved in a legislature:^[3]

• Formalistically: how the rules of the legislature ensure representation of constituents;
• Symbolically: how the constituents perceive their representatives;
• Descriptively: how well the composition of the legislature matches the demographics of the wider society;
• Substantively: how well representatives actually respond to the needs of their constituents;
• Collectively: how well the representatives represent the interests of the society as a whole.

One of the major functions of a legislature is to discuss and debate issues of major importance to society.^[3] This activity can take place in two forms. In debating legislatures, such as theParliament of the United Kingdom, the floor of the legislature frequently sees lively debate.^[3] In contrast, in committee-based legislatures like theUnited States Congress, deliberation takes place in closed committees.^[3]

While legislatures have nominally the sole power to create laws, the substantive extent of this power depends on details of the political system. InWestminster-style legislatures the executive (composed of the cabinet) can essentially pass any laws it wants, as it usually has a majority of legislators behind it, kept in check by the party whip, while committee-based legislatures in continental Europe and those inpresidential systems of theAmericas have more independence in drafting and amending bills.^[5]

The origins of thepower of the purse which legislatures typically have in passing or denyinggovernment budgets goes back to the European assemblies of nobility which themonarchs would have to consult before raising taxes.^[6] For this power to be actually effective, the legislature should be able to amend the budget, have an effective committee system, enough time for consideration, as well as access to relevant background information.^[6]

There are several ways in which the legislature can hold the executive branch (the administration or government) accountable. This can be done through hearings,questioning,interpellations,votes of confidence, the formation of committees.^[7] Parliaments are usually ensured with upholding the rule of law, verifying that public funds are used accountably and efficiently as well as make government processes transparent and actions so that they can be debated by the public and its representatives.^[7]

Agora notes that parliamentary systems or political parties in which political leaders can influence or decide which members receive top jobs can lead to passivity amongst members of the party and less challenging of leadership.^[7] Agora notes that this phenomenon is acute if the election of a member is dependent on the support of political leadership.^[7]

In contrast todemocratic systems, legislatures underauthoritarianism are used to ensure the stability of the power structure by co-opting potential competing interests within the elites, which they achieve by:^[8]

• Providing legitimacy;
• Incorporating opponents into the system;
• Providing some representation of outside interests;
• Offering a way to recruit new members to the ruling clique;
• Being a channel through which limited grievances and concessions can be passed.

Each chamber of the legislature consists of a number of legislators who use some form ofparliamentary procedure to debate political issues and vote on proposed legislation. There must be a certain number of legislators present to carry out these activities; this is called aquorum.

Some of the responsibilities of a legislature, such as giving first consideration to newly proposed legislation, are usually delegated tocommittees made up of a few of the members of the chamber(s).

The members of a legislature usually represent differentpolitical parties; the members from each party generally meet as acaucus to organize their internal affairs.

Legislatures vary widely in the amount ofpoliticalpower they wield, compared to other political players such asjudiciaries,militaries, andexecutives. In 2009, political scientistsM. Steven Fish andMatthew Kroenig constructed a Parliamentary powers index in an attempt to quantify the different degrees of power among national legislatures. The GermanBundestag, theItalian Parliament, and the MongolianState Great Khural tied for most powerful, while Myanmar'sHouse of Representatives and Somalia'sTransitional Federal Assembly (since replaced by theFederal Parliament of Somalia) tied for least powerful.^[9]

Some political systems follows the principle oflegislative supremacy, which holds that the legislature is the supreme branch of government and cannot be bound by other institutions, such as the judicial branch or a writtenconstitution. Such a system renders the legislature more powerful.

Inparliamentary andsemi-presidential systems ofgovernment, theexecutive is responsible to the legislature, which may remove it with avote of no confidence. On the other hand, according to theseparation of powers doctrine, the legislature in apresidential system is considered an independent and coequal branch of government along with both thejudiciary and the executive.^[10] Nevertheless, many presidential systems provide for theimpeachment of the executive for criminal or unconstitutional behaviour.

Legislatures will sometimes delegate their legislative power toadministrative orexecutive agencies.^[11]

Legislatures are made up of individual members, known aslegislators, whovote on proposed laws. A legislature usually contains a fixed number of legislators; because legislatures usually meet in a specific room filled with seats for the legislators, this is often described as the number of "seats" it contains. For example, a legislature that has 100 "seats" has 100 members. By extension, anelectoral district that elects a single legislator can also be described as a "seat", as, for example, in the phrases "safe seat" and "marginal seat".^[12]

After election, the members may be protected byparliamentary immunity orparliamentary privilege, either for all actions the duration of their entire term, or for just those related to their legislative duties.

A legislature maydebate andvote uponbills as a single unit, or it may be composed of multiple separateassemblies, called by various names includinglegislative chambers,debate chambers, andhouses, which debate and vote separately and have distinct powers. A legislature which operates as a single unit isunicameral, one divided into two chambers isbicameral, and one divided into three chambers istricameral.

In bicameral legislatures, one chamber is usually considered theupper house, while the other is considered thelower house. The two types are not rigidly different, but members of upper houses tend to be indirectly elected or appointed rather than directly elected, tend to be allocated byadministrative divisions rather than by population, and tend to have longer terms than members of the lower house. In some systems, particularlyparliamentary systems, the upper house has less power and tends to have a more advisory role, but in others, particularlyfederalpresidential systems, the upper house has equal or even greater power.

Infederations, the upper house typically represents the federation's component states. This is also the case with the supranational legislature of theEuropean Union. The upper house may either contain the delegates of state governments – as in the European Union and in Germany and,before 1913, in the United States – or be elected according to a formula that grants equal representation to states with smaller populations, as is the case in Australia and the United States since 1913.

Tricameral legislatures are rare; theMassachusetts Governor's Council still exists, but the most recent national example existed in the waning years of White-minority rule inSouth Africa.Tetracameral legislatures no longer exist, but they were previously used in Scandinavia. The only legislature with a number of chambers bigger than four was theFederal Assembly of Yugoslavia; initially established as a Pentacameral body in 1963, it was turned into a hexacameral body in 1967.

Legislatures vary widely in their size. Amongnational legislatures, China'sNational People's Congress is the largest with 2,980 members,^[13] whileVatican City'sPontifical Commission is the smallest with 7.^[14] Neither legislature is democratically elected: The Pontifical Commission members are appointed by the Pope and theNational People's Congress isindirectly elected within the context of aone-party state.^[13][15]

Legislature size is a trade off between efficiency and representation; the smaller the legislature, the more efficiently it can operate, but the larger the legislature, the better it can represent the political diversity of its constituents. Comparative analysis of national legislatures has found that size of a country'slower house tends to be proportional to thecube root of itspopulation; that is, the size of the lower house tends to increase along with population, but much more slowly.^[16]

• List of legislatures by country
• List of legislative buildings
• Election apportionment diagram
• Evidence-based legislation
• Highest organ of state power