Federations often have a bicameral parliament: one house speaks for the nation itself, whereas the other one speaks for the subjects within the federation (it could be summoned by the means of the popular vote, like the U.S. Senate since Amendment XVII of 1912-13, or appointed by subject governments, like the Russian Federal Council).

The state legislature in the U.S. got me thinking: why do non-federations (unitary governments or U.S. states) need the upper house? This was asked on Quora, yet the answers seemed quite shaky. I liked this one:

The point of a bicameral legislature at any level is to have one body that responds quickly to political demands, and another that moves more slowly and carefully. Sometimes what people are screaming for just isn't a good idea. A more deliberative body that doesn't have to face re-election immediately can take a longer term view. -- Louis Cohen.

Yet it seems (to me) that such a system would give rise to in-all-earnest populism during the upper house elections.

So, why do non-federations need the upper house? If Louis Cohen got it right in his answer, am I right to reckon populism to be a standing problem in such a system?

Besides, Nebraska got rid of the upper (well, the lower) House back in 1937. How is this working out for them?

  • 2
    At least in the US, having a population-based House and state-based Senate was more of a compromise (due to a failure to agree on one or the other) than a goal.
    – chepner
    Commented Jan 13, 2021 at 18:52
  • 3
    Why stop at two? en.wikipedia.org/wiki/Tricameralism Commented Jan 13, 2021 at 18:58
  • They don't, partly because "one house speaks for the nation itself, the other for the subjects within the federation" is so wrong. Take most obviously my own Great Britain and within that, England - on which all English-speaking nations base their constitutions. That the United Kingdom includes England, Scotland, Wales and Northern Ireland makes no difference. Since centuries before those areas were forced together, England had a bicameral parliament. That, not UKGB, is considered "The Mother of Parliaments", model for half the world. Commented Jan 15, 2021 at 20:44

5 Answers 5


The UK has been a unitary state for much of its history, and its Parliament has had two Houses for most of that time.

The role of the House of Lords is as the quote in the question states. It's not subject to to either the political or electoral pressures of the Commons (given that it's entirely unelected), so it is able to deliberate on matters at length - whether that's scrutinising legislation, or questioning government ministers, or debate matters of interest.

In addition, besides containing many former MPs and ministers, appointees to the House of Lords include a number of experts in their respective fields who are not full-time politicians. They're able to bring specialist knowledge when the House is considering matters within their area of expertise.

One of the arguments against having an elected upper house in the UK is the concern that it would become too similar in nature to the Commons, and that having to be elected would put off people (like experts) who would like to contribute part-time, but who don't want to be full-time legislators.

The UK is no longer a fully-unitary state, and the Scottish Parliament, Welsh Parliament and Northern Ireland Assembly are all unicameral. The UK Parliament can still legislate on any matter for the whole of the UK; but in practise it mostly limits itself to England, or to UK legislation in areas that are not devolved to the regional parliaments.


With a couple of exceptions where bicameral parliaments grew out of tradition (i.e. probably only England), at some point in history a select group of people from a state came together and began drawing up a constitution. This can be initiated from above (the German constitution of 1871) or from members of the public (the West German constitution of 1948). These people will discuss and argue how the political system of the state should be organised; sometimes with certain conditions imposed on them by the current ruler.

It would make little sense for two houses of parliament to be exactly the same, so if this group of deliberators decides to go for (or is asked to go for) a bicameral system, they will usually come up with some way of differentiating the two houses.

In a democratic (or pseudo-democratic) system of government, one of the houses will typically be your standard, fully elected parliament – like the US House of Representatives, the German Bundestag, the French Assemblée Nationale, the Japanese House of Representatives, etc. Unicameral legislatures are typically of this type (e.g. the parliament of Finland or the Riksdag of Sweden).

The differentiating element of the other house can be:

  • It is a wholly unelected body, meant to deliberate at length; ideally primarily interested in advancing the nation as a whole rather than one’s own re-election bid; often individual members representing certain groups of interest.

    Examples: the House of Lords, the (abolished) Bavarian Senate.

  • It is meant to represent the elected bodies of lower levels so that the national parliament is forced to listen to input from various parts of the country (this is often the case in federations).

    Examples: the French Senate, the German Bundesrat, the initial US Senate before Senators were elected by popular vote in the several states, the Council of the EU/European Council.

    A modification of this would be the case of the Australian or modern US Senate. These are bodies elected by popular vote but the individual states each have the same number of seats so that large states and small states are equal.

  • It is meant to be a chamber with longer terms, less frequent elections to provide continuity to the parliamentary system. This may be enhanced by introducing staggered terms, i.e. only half of the members (one third in the US Senate) being up for re-election at a given time.

    Examples: Australian Senate, Japanese House of Councillors

There are likely more possibilities but I don’t have the adequate examples on hand. In addition, as is evident by certain examples appearing in multiple sections these examples need not be mutually exclusive.


Many of the bicameral legislatures were probably created in imitation of the UK Parliament, and of other European parliaments which were formed on similar lines for similar reasons. If you look at the early history of the UK Parliament, the House of Lords (once the Crown Council) was not to be "another [body] that moves more slowly and carefully," although it may have filled that role after the Commons became more powerful. Originally the Lords were the people who controlled much of the military and economic power in the kingdom, the men (and they were all men then) who could provide soldiers and cash and whose opposition could cause a problem for the King. These were the people the King had to keep happy, as a group, to have a successful rule rather than an ongoing civil war. Even further back, they were William I's chief supporters, the men who had helped him to a kingdom in England. Their reward was having a say in how things were run. The Commons were a somewhat later development, a trade of influence for tax money.

Explicit design for a popular house and a slower reacting house that provides continuity and "wisdom" is a creation of the 18-century "Enlightenment" and is in significant part a justification of an already long-established pattern. That is more-or-less the justification of the US Framers, particularly well expounded in The Federalist, which is very much a product of the Enlightenment worldview. How much the US Congress has acted that way over the years could be argued.

There is also the idea that if two houses are chosen in different ways, tending to favor different power sources within a country, that tends to produce compromise rather than civil war. Again, it is not clear that this has usually worked as well as the theorists imagined it would. But it has worked well enough in many places that people have not gone to the effort of changing it.


The simple, additional answer besides "copies of UK", is that more countries have territorial representation than those which are formal federations. An example would be Spain--it has 17 autonomous regions (+2 such cities), but it's not a full-fledged federation. Basically, there's a spectrum of decentralization.

Slightly longer answer, based on one of those sources is that the reasons have been sometimes pegged into 4 categories:

  1. Chambers of review and reflection. They exist to improve the quality of legislation and to provide a forum in which appointed experts and elder statespersons can debate the technical details of legislation in a calm, informed manner, without challenging the primacy of the lower chamber in terms of policymaking. The members of such a chamber would mainly be recruited from within political, legal and administrative elites, and their powers might be limited to proposing amendments and delaying legislation.

  2. Chambers intended to provide territorial representation. These occur especially in federal systems, serving to protect the right and interests of the territorial units and to give them a say in legislation. Such chambers might be directly elected on a territorial basis, or chosen by the subnational legislatures, and they might have fairly extensive veto powers.

  3. Chambers which exist to provide breadth of representation. This can be achieved either by including certain minority communities or by giving an institutional voice to certain social, economic and cultural interests.

  4. Chambers based on the principle of democratic contestation. Such chambers provide a democratic check on incumbents. Second chambers in this last category are necessarily chosen by direct election (often using a different electoral system and/or electoral cycle to that used by the primary chamber) and might typically possess extensive veto powers.

Of course, these categories are not mutually exclusive, and in reality many second chambers play two or more complementary roles (see Table 4.1)

enter image description here

According to that source, there are some countries where the two chambers are practically duplicates of each other though. The example provided there is Romania. Looking through the Wikipedia article of that country's senate, it seems that in older constitutions their senate had seats for clergy etc., which in some sense copied the UK system, but there's no clear reason given why the senate was reconstituted in later times/constitutions. I guess it may have been because Romania has a semi-presidential system fairly inspired from France's which also has a Senate, but France's is elected indirectly, whereas Romania's is directly elected. (Aside: Romania's president has less powers than France's.) So I guess besides "UK copies", there are "France copies" as a tradition-type reason.

Somewhat (but not directly) related, there is actually an interesting paper that proposes that a concept of "semi-parliamentarism" justifies a 2nd chamber; this is defined as:

  1. There is no direct (or popular) election of the chief executive or head of state.
  2. The assembly has two directly elected houses.
  3. Only the lower house can dismiss the cabinet in a no-confidence vote.
  4. The upper house has veto power over ordinary legislation that is not merely suspensory and/or cannot be overridden by a simple or absolute majority in the lower house.

The core features of semi-parliamentary bicameralism are conditions (2) and (3): even though the upper house is directly elected, it does not participate in the no-confidence procedure.

Defined this way, this system is mutually exclusive with a semi-presidential one, because of condition 1. (The term "semi-parliamentary" term alas has had other definitions.)

According to the author of that paper, a not-strictly-federal country that qualifies for that definition of semi-parliamentarism is Japan.

  • I like the answers about "copying the UK", yet they got enough attention, unlike this one. I'm going to tick this it, although I +1ed every other one. My "Thank you" goes out to every answerer! Commented Jan 14, 2021 at 8:39

Because even unitary countries can be seen as federations, most of them are divided in regions and many have strong cultural differences between the regions.

The majority of the lower house usually is skewed because most of the population is concentrated in one area of the country, so the upper house or the senate with members elected on a regional basis would act as a counterbalance.

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .