March 29, 2005 by Paul McKeever
What are the alleged problems with Canada’s Single Member Plurality (“SMP”) system (often referred to as the “first past the post” system)? What are the proposed solutions?
Different alternative electoral systems address different problems, but several very different systems are being debated at present as though they address the same alleged problems. This brief primer describes the main electoral systems, and explains the alleged problems that each alternative to the SMP is designed to address.
1. SMP: Description
In the SMP system, one legislative seat is allocated to each geographically-defined electoral district. Federally, there are currently 308 electoral districts (a.k.a. “ridings”).
In the SMP system, the ballot in each riding contains a list of the candidates running in that riding. Voters entitled to vote in that riding mark ONE of the candidates’ names with an X. After the polls are closed, the candidate whose name was Xed on the greatest number of valid ballots wins the seat in that riding.
2. SMP: ALLEGED PROBLEMS AND PROPOSED SOLUTIONS
(a) The “Wasted Vote”
When there are only two candidates on a ballot (e.g., in a two-party system), one casts ones vote for the candidate one most wants to win: ones vote is not “wasted” in any sense. However, when three or more candidates are on a ballot, a voter may feel that his favourite candidate has little chance of winning. Under the SMP, such a voter may decide to vote strategically: he may decide to vote only for one of the subset of candidates who he thinks stand a chance of winning. This way, he thinks, he will not be “wasting” his vote. The problem, however, is that by strategically voting, the voter might get the legislator he voted for, but not the legislator he actually wanted most. The primary solution to the wasted vote involves using a “preferential ballot” in conjunction with an alternative vote-counting system
Preferential Ballot Systems
On a preferential ballot, voters rank some or all of the candidates, rather than just choosing one. When used in conjunction with an appropriate vote-counting system, a preferential ballot solves the “wasted vote” phenomenon.
There are two main electoral systems that use a preferential ballot: the Alternative Vote (“AV”) system, and the Single Transferable Vote (“STV”) system. However, counting of the ballots differs between the AV and the STV. Here’s a comparison of the two systems, quoted from an as yet unpublished paper I am working on:
“In the AV system, like in the SMP system, one individual is selected from each electoral district. If at least fifty percent plus one of the ballots all rank a given candidate as their first preference, the candidate is immediately elected. However, if fewer than fifty percent plus one of the ballots rank a given candidate as their first preference, the candidate with the lowest number of first preferences is “eliminated” from the count. The ballots that gave first preference to the eliminated candidate are then assigned to the remaining candidates according to the second preferences indicated on those ballots. The process of eliminating last-place candidate and redistributing their ballots process is repeated until one candidate has at least fifty percent plus one of the ballots.
The STV system differs from the AV system in two key ways. First, in the STV system, electoral districts are bigger, and voters select more than one individual to become law-makers. Second, the STV tallies the ballots in a way that tends to result in “proportional representation” (discussed below). Specifically, in the STV system, the greater the number of seats that are allocated to an electoral district, the smaller is the number of votes that a candidate must receive to win a seat (for convenience, I will hereinafter refer to that number as the “Threshold”). Specifically, in the STV system, the Threshold is equal to 1 + [total number of votes cast] / [number of seats + 1]. As in the AV system, last-placed candidates are eliminated and their ballots are redistributed to the remaining candidates until the number of votes received by a candidate meets or exceeds the Threshold and he wins a seat. However, unlike in the AV system, if a candidate who has won a seat received more than enough votes to meet the Threshhold, his “Surplus” ballots continue are transferred to the remaining candidates according to the next preference on those ballots. In fact, all of his ballots are added, not just the a number of ballots equal to the Surplus, but the value of the votes on those ballots is reduced so that the total value of the votes on those ballots is equal to the number of Surplus votes: each ballot adds a fraction of a vote equal to the number of Surplus votes divided by the Threshold. If, after transfering all of the Surplus votes, the remaining candidates still lack enough votes to win a seat, the candidate with the fewest votes is eliminated and his ballots are redistributed among the remaining candidates according to the next preference indicated on each ballot. The process of eliminating candidates and redistributing the votes of candidates who win seats or who are eliminated continues until all of the seats for that electoral district are filled.
Both the AV system and the STV system eliminate the fear of the wasted vote. Because both use a preferential ballot, voters can rank their preferences. Because, in each system, a ballot is counted even if its first-ranked candidate loses, voters do not have to fear that their vote will be wasted if they give their highest rank to a candidate who is unlikely to win. The voter, in the AV and STV systems, is not cowed, by polls, media opinion, or next-door neighbours into caring whether or not his favoured candidate is likely to win. Strategic voting is forced to take a back seat to the voter’s conscience. The voter does not need to compromise his beliefs and commitments. The voter can, with the AV and STV systems, respect and value elections.”
(b) Minority Rule / Forcing Compromises
Under the SMP system, a the winning candidate is the candidate that received more votes than any other candidate on the ballot. When there are only two candidates on the ballot, the winner needs 50% + 1 of the votes. But the number of votes needed to win decreases with each increase in the number of candidates. Specifically, the minimum percentage of the vote required to win in the SMP system can be as low as (100 / #of candidates) + 1. So, for example, if there are 10 candidates on the ballot then, if the votes are evenly distributed among the candidates, the winner might win with as little as 10% plus one of the votes.
There are those who dislike this aspect of SMP. The most common argument is that the SMP allows a minority of voters to win a majority of seats in the legislature. Equating the voters’ winning of seats with the voters’ control of the legislature (which, I would submit, is a laughable conclusion), those who oppose this aspect of the SMP say that it violates the principle of “majority rule”: the idea that government should do what the majority of VOTERS want it to do.
However, there is another argument raised against SMP. Specifically, it is said that majority governments are bad because they discourage compromise and collaboration. These advocates prefer perpetual minority governments so that, in effect, radical agendas cannot prevail. Another way to put this, bluntly, is that the left doesn’t want a principled party to win a majority and then not compromise its agenda with those who are opposed to the winning party’s principles.
There are two main electoral systems proposed to “solve” the lack of PR that can occur with the SMP in a multi-party system. Both cause PR electoral outcomes, and both make majority governments the exception instead of the rule: the STV and List Systems
I have described the STV, above. The key thing to remember when comparing the STV with a List system is that, under the STV, the voter votes for his local candidates, not for parties.
List systems are sometimes referred to as “pure PR” systems. In list systems, the voter votes for a party (in some versions of the List system, they also get to indicate a preference of candidates within that party). Each party then is given a percentage of seats roughly equal to the percentage of votes received by the party.
The key difference between the STV and List systems is that List systems give parties the power to decide who will fill each of the seats won by the party. The NDP and Green parties, in Canada, have said that they prefer the List systems because they want to allocate the seats they win on the basis of such things as sex and race: they want to use “affirmative action” (i.e., discrimination) in the selection of MPs. Because the STV provides a PR outcome without allowing parties to choose the candidates, the Greens and NDP oppose the STV.