Editing Parallel voting (section)

== Advantages and disadvantages ==
=== Representation for smaller parties ===
The major critique of parallel systems is that they cannot guarantee overall proportionality. Large parties can win very large majorities, disproportionate to their percentage vote.

Parallel voting systems allow smaller parties that cannot win individual elections to secure at least some representation in the legislature; however, unlike in a proportional system they will have a substantially smaller delegation than their share of the total vote. This is seen by advocates of proportional systems to be better than elections using only first-past-the-post, but still unfair towards constituents of smaller parties. If there is also a threshold for list seats, parties which are too small to reach the threshold are unable to achieve any representation, unless they have a very strong base in certain constituencies to gain individual seats. 

Smaller parties are still disadvantaged as the larger parties still predominate. Voters of smaller parties may tactically vote for candidates of larger parties to avoid wasting their constituency vote. If the smaller party close to the threshold may refrain from voting for their preferred party in favour of a larger party to avoid wasting their list vote as well. In countries where there is one dominant party and a divided opposition, the proportional seats may be essential for allowing an effective opposition.

Those who favour majoritarian systems argue that supplementary seats allocated proportionally increases the chances that no party will receive a majority in an assembly, leading to [[Minority government|minority]] or [[Coalition government|coalition governments]].{{Citation needed|date=April 2022}}; the largest parties may need to rely on the support of smaller ones in order to form a government. Those who favour proportional representation see this as an advantage as parties may not govern alone, but have to compromise. It is also argued that parallel voting does not lead to the degree of fragmentation found in party systems under pure forms of [[proportional representation]].<ref name="reynolds112">Reynolds et al (2008), ''Electoral System Design: The New International IDEA Handbook'', Sweden: International Institute for Democracy and Electoral Assistance, pg. 112</ref>

=== Two types of representatives ===
Because voters have two votes, one for a constituency candidate and one for a list, there is a critique that two classes of representatives will emerge under a parallel voting system: with one class beholden to their electorate seat, and the other concerned only with their party. Some consider this as an advantage as local as well as national interests will be represented. Some prefer systems where every constituency and therefore every constituent has only one representative, while others prefer a system where every MP represents the electorate as a whole as this is reflected in the electoral system as well.

=== Compared to MMP and AMS ===
Parallel systems are often contrasted with [[Mixed-member proportional representation|mixed-member proportional systems]] (MMP) or the [[additional member system]] (AMS). There are a unique set of advantages and disadvantages that apply to these specific comparisons.

A party that can [[gerrymander]] local districts can win more than its share of seats. So parallel systems need fair criteria to draw district boundaries. (Under MMP a gerrymander can help a local candidate, but it cannot raise a major party’s share of seats, while under AMS the effects of gerrymandering are reduced by the compensation)

[[Japan]], and subsequently [[Thailand]] and [[Russia]] adopted a parallel system to provide incentives for greater party cohesiveness.<ref>{{Cite book |date=2016 |title=Mixed-Member Electoral Systems in Constitutional Context |url=http://dx.doi.org/10.1353/book.52095 |doi=10.1353/book.52095|isbn=9780472121588 }}</ref> The party is sure to elect the candidates at the top of its list, guaranteeing safe seats for the leadership. By contrast, under the MMP or AMS system a party that does well in the local seats will not need or receive any compensatory list seats, so the leadership might have to run in the local seats.

Certain types of AMS can be made ''de facto'' parallel systems by tactical voting and parties using decoy lists, which (other) MMP systems generally avoid. This specific type of tactical voting does not occur in parallel voting systems as there is no interaction between its systems to exploit in a way that makes it irrelevant. However, other types of tactical voting (such as compromising) are more relevant under parallel voting, than under AMS, and are virtually irrelevant under MMP.{{Citation needed|date=April 2022}} Tactical voting by supporters of larger parties in favour of allied smaller parties close to a threshold, to help their entry to parliament are a possibility in any parallel, AMS or MMP system with an electoral threshold.

Parallel systems support the creation of single-party majorities more often than MMP or AMS systems, this may be a positive or a negative depending on the view of the voter.