Introduction

The constitutional decision of whether to establish a bicameral (two chamber) or
unicameral (one chamber) system is an important one.  Although there are no simple
answers to this question, some generalizations can be made.  While federal systems tend
to have bicameral legislatures, presumably to ensure representation of states or provinces,
smaller countries with unitary governments tend to establish unicameral legislatures.  It is
also generally the case that larger states, with larger populations, tend to have bicameral
systems.

Bicameralism

A bicameral legislature has two chambers, often classified as the lower and upper house.
The composition of the lower chambers (with such names as the House of
Representatives, House of Commons, Chamber of Deputies and Federal Assembly) is
generally proportionally based on population whereby each elected member represents a
certain number of citizens. Upper chambers (sometimes called a Senate, House of Lords
or Federal Council) vary considerably in their composition and in the manner in which
their membership is selected.  Some upper chambers represent regional and state
divisions, such as in the United States and Germany, while others, like the United
Kingdom and Canada, are appointed (or hereditary).  In general, upper chambers tend to
be the smaller legislative body whose members serve longer terms than their lower
chamber counterparts.

In bicameral systems, the authority of the two chambers varies widely from country to
country.  In most cases, the upper chamber has more limited authority than the lower
chamber.  This limitation on the upper chamber's authority may mean that it only has the
power to delay or to review legislation adopted by the lower chamber, and/or that it has
more limited power in budget and fiscal issues.  On the other hand, there are also
bicameral systems, like that of the United States, in which the two chambers have equal
or offsetting powers and both chambers have equal power to review, amend and adopt
legislation.

The advantages attributed to bicameralism are its ability to:

formally represent a more diverse constituency in a legislative chamber, whether it be on
behalf of the states, provinces or territories, or a specific (ethnic- or class-based) segment
of the population;
facilitate a more deliberative approach to legislation;
hinder the passage of flawed or impulsive legislation;
and provide an opportunity for enhanced control of the executive branch.

Unicameralism

Unicameral legislatures have one chamber and are frequently found in countries with
unitary -- rather than federal -- governmental systems.   A study conducted of 66 unitary
states showed that 54 had unicameral legislatures and only 12 had bicameral systems.
Unicameral legislatures comprise a single, popularly-elected chamber.  In 1976 Portugal
adopted a new constitution with a unicameral system; as a country with a population of
10 million Portugal is today the largest Western democracy without a second chamber.

The advantages attributed to unicameralism are its ability to:

rapidly enact proposed legislation because there is no need to reconcile divergent bills
produced in different chambers;
provide for increased accountability because elected representatives cannot point to the
other chamber if legislation is not approved and there are fewer elected officials for the
population to monitor, and;
be less costly to the government and tax payers.

Cameral Change

Among the newly emerging democratic states, several have replaced unicameral
legislatures with bicameral ones.  One leading example is Romania (with a population of 8
million) which, after the fall of communism in 1989, established a two-chambered
institution.  Romanian legislators reported that they favored bicameralism because they felt
that it would prevent the concentration of power in the executive branch and would
improve the quality of legislation.  The 143-member Senate and 328-member Chamber
of Deputies have roughly similar powers and are both elected for four-year terms through
proportional representation. Romanian critics of this arrangement argue that the chambers
are redundant because they have the same authority and the same electoral base.  Those
critics also note that deadlock between the two houses has undermined the legislature's
ability to act as a check on the executive and has diminished the institution's public
credibility.
Kurgyzstan has also adopted a bicameral system in the post-communist era and, perhaps
in part due to vagueness in the constitutional text itself, and legislators are still addressing
the problem of  resolving differences in legislative texts adopted by the two chambers.

While some new states have moved towards bicameralism, other established legislatures
have moved in the opposite direction.  Sweden, a country with a population the size of
Romania's, adopted a bicameral legislature in 1867.
In 1971, however, in response to legislative stalemate and political stagnation, Sweden's
political parties agreed to amend the constitution and provide for a one chamber
legislature.  Similarly,  in 1950, after 96 years of a bicameral legislature, New Zealand
converted to a unicameral system because of a consensus that the appointed upper house
was politically and legislatively irrelevant.


Conclusion

In sum, bicameral legislatures  tend to be found in larger and more heterogeneous
countries and unicameral legislatures  in relatively small and homogeneous countries.  As
some experts have pointed out, a strong case for bicameralism can be made when an
upper house represents regions such as states or provinces or distinct ethnic groups in a
society that is deeply divided.  However, these experts also emphasize that even in
federal and/or divided countries, bicameralism does not make sense if the two houses are
elected in the same fashion.

Submitted by Susan R. Benda
National Democratic Institute for International Affairs
1717 Massachussetts Avenue, NW Fifth Floor
Washington, DC 20036
Tel: 202-328-3136
Fax: 202-265-0168
E-mail: demos@ndi.org