thumb|right|Vote cast against [[Themistocles. A quorum of 6,000 was required for ostracism under the Athenian democracy, according to Plutarch; a similar quorum was necessary in the following century for grants of citizenship.]]
A quorum is the minimum number of members of a group necessary to constitute the group at a meeting. In a deliberative assembly (a body that uses parliamentary procedure, such as a legislature), a quorum is necessary to conduct the business of that group. In contrast, a plenum is a meeting of the full (or rarely nearly full) body. A body, or a meeting or vote of it, is quorate if a quorum is present (or casts valid votes).
The term quorum is from a Middle English wording of the commission formerly issued to justices of the peace, derived from Latin quorum, "of whom", genitive plural of qui, "who". As a result, quora as plural of quorum is not a grammatically well-formed Latin-language construction. In modern times, a quorum might be defined as the minimum number of voters needed for a valid election. Quorums are often part of parliamentary procedure.
In Robert's Rules of Order
According to Robert, each assembly determines the number of members that constitutes a quorum in its governing documents (such as in its constitution, charter, bylaws or standing orders). The quorum may also be set by law. Robert's Rules of Order Newly Revised states that the quorum set in an organization's bylaws "should approximate the largest number that can be depended on to attend any meeting except in very bad weather or other extremely unfavorable conditions." In a committee of the whole or its variants, a quorum is the same as the assembly unless otherwise provided.
In online groups, a quorum has to be determined in a different manner since no one is actually "present". The rules establishing such groups would have to prescribe this determination. An example is that a quorum in such groups could be established as "present" if enough members state that they are "present" at the designated meeting time.
Determination of a quorum
The chairperson of the group has the responsibility to determine if a quorum is present. In addition, any member can raise a point of order about an apparent absence of a quorum. Because it is difficult to determine exactly when a quorum was lost, points of order relating to the absence of a quorum are "generally not permitted to affect prior action; but upon clear and convincing proof, such a point of order can be given effect retrospectively by a ruling of the presiding officer, subject to appeal."
Any other business that is conducted is not valid unless it is ratified at a later meeting where a quorum is present. However, there is no obligation to ratify such action and those responsible may be punished for their actions. This procedure does not exist in ordinary societies, since voluntary associations have no coercive power.
No-show paradox
Quorums have been criticized by social choice theorists for their pathological behavior, including an absurd result called a no-show paradox, where a proposal may pass because too many members oppose it. This has led many jurisdictions and bodies to replace traditional quorums with quorums of votes in favor, i.e. a requirement that any proposal be supported by a certain share of the entire membership to pass (e.g. 25% of all members). In the senate, the quorum was amended down to one-quarter by the Senate (Quorum) Act 1991, so 19 senators is a quorum. The quorum includes the occupant of the Chair, and is not reduced by the death or resignation of a member or senator.
If at the beginning of a sitting the quorum is not met, the bells are rung for five minutes and a count is then taken; if the quorum is still not met the sitting is adjourned until the next sitting day. During the sitting, any MP or senator may draw attention to the lack of quorum in which the bells are rung for four minutes, and if a quorum is still not met the sitting is adjourned.
Although quorum-busting is virtually unheard of in Australia, it is not unknown for parties to deliberately use quorum counts as a disruptive tactic and there have been some suggestions to enact rules to restrict this practice; however, this is very difficult due to the explicit mention of a quorum in the constitution. It is considered disorderly to call attention to quorum when one exists, and members or senators who do so can be punished.
State and territorial quorums
{| class="wikitable"
|-
! State/Territory !! Legislative Council !! Legislative Assembly / House of Assembly
|-
| New South Wales || 9 (of 42) || 21 (of 93)
|-
| Victoria || One-third (14 of 40)||21 (of 88)
|-
| Queensland || N/A || 17 (of 93)
|-
| Western Australia || one-third + President (13 of 36)|| one-third + Speaker (of 22)|| 17 (of 47)
|-
| Tasmania || 7 (of 15)|| 14 (of 25)
|-
| Australian Capital Territory || N/A || majority (13 of 25)
|-
| Northern Territory || N/A || 10 (of 25)
|}
Austria
In the National Council of Austria at least one-third of the representatives must be present, so that they may decide on a simple law (participation quorum of 33.3%). At least half of the members must participate if a constitutional law should pass the parliament (participation quorum of 50% based on the total number of members). Over and above that, constitutional laws require the consent of at least two-thirds of the members present (quorum agreement of 66.6% based on the number of voting present).
Canada
In Canada, the Constitution Act, 1867 sets quorum for sittings of the House of Commons of Canada at 20 MPs. If a member calls for quorum to be counted and a first count shows there are fewer than 20 members, bells are rung to call in the members; if after 15 minutes there are still fewer than 20 members, the session is adjourned to the next sitting day; the members present sign a roll on the table of the house, and this list is included in the Journal of the House. There is no need for quorum when the attendance of the House is requested in the Senate of Canada, for example, when royal assent is being given to bills. The quorum of the Senate is 15.
Provincial and territorial quorums
{| class="wikitable"
|-
! Province/Territory !! Quorum
|-
| Alberta || 10
|-
| British Columbia || 10
|-
| Manitoba || 10
|-
| New Brunswick || 14
|-
| Newfoundland and Labrador || 15
|-
| Northwest Territories || majority
|-
| Nova Scotia || 15
|-
| Nunavut || majority
|-
| Ontario || 12
|-
| Prince Edward Island || 10
|-
| Quebec || 21
|-
| Saskatchewan || 15
|-
| Yukon || majority
|}
Germany
In the German Bundestag more than half of the members (currently 369 out of 736) must be present so that it is empowered to make resolutions. It is however common that fewer members are present, because they can still make effective decisions as long as no parliamentary group or 5% of the members of the parliament are complaining about the lack of quorum. This, in rare cases, is used by opposition parties to delay votes.
Hong Kong
Article 75 of the Basic Law of Hong Kong stipulates that the quorum required for the meetings of the Legislative Council of Hong Kong (LegCo) as "not less than one-half of its members". Between 1997 and 2012 the quorum was 30, and since 2012 it has been 35. Prior to 1997 transfer of sovereignty over Hong Kong, the quorum was set at 20.
The quorum for the panels, committees and subcommittees is, nevertheless, one-third or three members, whichever the greater, as according to the Rules of Procedure. The three standing committees, namely, the Finance Committee, the Public Accounts Committee and Committee on Members' Interests, is exceptional that the quorums are 9, 3 and 3 respectively.
India
Article 100 of the Constitution of India stipulates that at least 10% of total number of members of the House must be present to constitute the quorum to constitute a meeting of either House of Parliament. For example, if the House has the total membership of 250, at least 25 members must be present for the House to proceedings with its business.
If at any time during a meeting of a House there is no quorum, the chairman has to either adjourn the House or suspend it until there is a quorum. Some procedures do require minimum participation: a motion without notice to suspend the Standing Orders can be moved only if at least 60 members are present, and a personal vote requires at least 20 participating members.
Pakistan
Article 55 of the constitution of Pakistan, states that, if at any time during a sitting of the National Assembly the attention of the person presiding is drawn to the fact that less than one-fourth of the total membership of the Assembly is present, he shall either adjourn the Assembly or suspend the meeting until at least one-fourth of such membership is present, which currently comprises 84 out of total 336.
Philippines
In Congress of the Philippines, majority of the membership (13 in the Senate and 160 in the House of Representatives) is needed to muster a quorum. If someone contests the lack of quorum, a roll call shall be done, and if there is indeed less than a majority of members present, the meeting shall be adjourned.
Both majority and minority blocs in Congress have used the lack of quorum in defeating bills that they do not want to be passed without putting it to a vote. After an election during the lame-duck session, quorums are notoriously difficult to muster, more so in the House of Representatives as winning incumbents may opt to go on vacation, and defeated incumbents may opt not to show up.
In Avelino vs. Cuenco, the Supreme Court ruled that members outside the Philippines are not included in the determination of quorum.
Turkey
According to article 96 of the Turkish Constitution, unless otherwise stipulated in the Constitution, the Turkish Grand National Assembly shall convene with at least, one-third of the total number of members (184 out of 550) and shall take decisions by an absolute majority of those present; however, the quorum for decisions can, under no circumstances, be less than a quarter plus one of the total
number of members (138 out of 550).
Before the constitutional referendum of 2007, there was a quorum of two-thirds required in the Turkish Parliament: after opposition parties used the quorum to deadlock the presidential election of 2007, making it impossible for the parliament to choose a president, the ruling AK party proposed a referendum to lower the quorum to prevent a repeat of this event. Nearly seventy percent of the participants supported the constitutional changes.
United Kingdom
In the Parliament of the United Kingdom, the House of Commons has a quorum of 40 MPs, including the Speaker, out of 650 members of the House. There is no need for a quorum to be present at all times: Commons debates could theoretically continue even if only one MP and the Speaker were present.
However, if a division is called and fewer than 40 MPs are present, then a decision on the business being considered is postponed and the House moves on to consider the next item of business.
The quorum for votes on legislation in the House of Lords is 30, but just three of the 753 peers, including the Lord Speaker, are required to be present for a debate to take place.
Historically, the quorum was a select group of the justices of the peace in each county in early modern Britain. In theory, they were men experienced in law, but many of the quorum were appointed because of their status. Some legislation required the involvement of a member of the quorum (e.g., granting a license to a badger). In practice, they increasingly were not qualified, as the proportion in the quorum rose faster than the proportion who were called to the bar or practising lawyers. By 1532, an average 45% of justices of the peace nationally were of the quorum. In Somerset, the proportion rose from 52% in 1562 to 93% in 1636. By then, most of those not on the quorum were new to the bench. Sometimes justices of the peace were removed from the quorum as a disciplinary measure less drastic than removal from the bench.
United Nations
The large deliberative bodies of the United Nations (the General Assembly and Economic and Social Council, as well as their subsidiary organs) generally require the attendance of one-third of the membership (currently 65 states in the General Assembly and 18 in ECOSOC) to conduct most business, but a majority of members (currently 97 states in the General Assembly and 28 states in ECOSOC) in order to take any substantive decisions. The rules of the United Nations Security Council make no provisions for quorum, but nine votes are in all cases required to pass any substantive measure, effectively meaning that a meeting with fewer than nine members in attendance is pointless.
United States
Article I, Section 5, Clause 1 of the United States Constitution provides that "Each House shall be the Judge of the Elections, Returns and Qualifications of its own Members, and a Majority of each shall constitute a Quorum to do Business..."
Therefore, in both the House of Representatives and the Senate, a quorum is a simple majority of their respective members (currently 218 in the House and 51 in the Senate).
The only exceptions are those stated in the Twelfth Amendment:
- In cases where no candidate for President of the United States receives a majority in the Electoral College, the election is decided by the House of Representatives, in which case "a quorum for this purpose shall consist of a member or members from two-thirds of the states" (a possible quorum as low as 34).
- In cases in which no candidate for Vice President of the United States receives a majority in the Electoral College, the election is decided by the Senate, in which case "a quorum for the purpose shall consist of two-thirds of the whole number of Senators" (a quorum of 67).
The Senate has the additional ordinary requirement in Rule VI of its Standing Rules that "A quorum shall consist of a majority of the Senators duly chosen and sworn."
Call of the house in the United States Senate
In the United States Senate, the procedure was last used in the early morning hours of 25 February 1988.
Senator Robert C. Byrd of West Virginia, then the Senate Majority Leader, moved a call of the house after the minority Republicans walked out of the chamber in an attempt to deny the Senate a quorum after Senate aides began bringing cots into the Senate cloakrooms in preparation for an all-night session over campaign finance reform for congressional elections.
Byrd's motion was approved 45-3 and arrest warrants were signed for all 46 Republicans: Senate Sergeant-at-Arms Henry K. Giugni and his staff searched the Capitol's corridor and Senate office buildings for absent Senators, and after checking several empty offices, spotted Senator Steve Symms of Idaho, who fled down a hallway and escaped arrest. After a cleaning woman gave a tip that Senator Robert Packwood of Oregon was in his office, Giugni opened the door with a skeleton key. Packwood attempted to shove the door closed, but Giugni and two assistants pushed it open. Packwood was subsequently carried feet-first into the Senate chamber by three plainclothes officers and sustained bruised knuckles.
Prior to 1988, the last time the procedure had been used was during a 1942 filibuster over civil rights legislation: