Instant Runoff Voting, Plurality Results and Majority Failure
An Instant Runoff Voting Majority is not what you think
One of the claims in favor of instant runoff voting is that it provides a majority winner.
That is true only if you redefine what "majority winner" means.
In San Francisco,"majority" is of the "continuing" ballots, not a majority of all ballots:
"If no candidate receives a majority of votes from the continuing ballots after a candidate has been
eliminated and his or her votes have been transferred to the next-ranked candidate, the continuing
candidate with the fewest votes from the continuing ballots shall be eliminated. All votes cast for that
candidate shall be transferred to the next-ranked continuing candidate on each voter's ballot.
This process of eliminating candidates and transferring their votes to the next-ranked continuing candidates
shall be repeated until a candidate receives a majority of the votes from the continuing ballots."
SEC. 13.102. - INSTANT RUNOFF ELECTIONS.(D) go to this link and type in the SEC. 13.102 in search box.
In other words, the majority consists of the votes left after others are eliminated.
The elimination of ballots and the exhaustion of ballots (the point a ballot does not have choices marked)
is part of the reason that in many instant runoff voting elections often suffer majority failure.
Bob Kiss had 4313 - or 48.41% of the original 8909, not 51.5%.
Kurt Wright had 4061 - or 45.58% of the original 8909, not 48.5%.
That is because the total number of votes for these two candidates in this round is 8374 -
or 535 less than the original 8909 cast in the first round.
That is why an IRV win is not a true majority win in all but one or two cases because you
never really get a true majority of the first round votes cast.
Pierce County Washington
December 7, 2008 2 out of 3 Pierce County RCV "winners" don't have a true majority
Peirce County WA claims to have winners in their RCV races -
but were they real majority wins?
....In order to get a true majority, the winner would have needed 131,224 votes.
The person who led the race in all 4 rounds "won" the RCV race in the 4th round
with 98,366 - 32,858 short of a true majority....
Cary, North Carolina
IRV was sold to Cary North Carolina as providing a 50% + 1 majority win,
along with the other false but clever claims.
From the 2007 powerpoint presentation given to the Cary Town Council to persuade them to volunteer for the IRV pilot
From Page 4:"It preserves majority rule by ensuring winners must have 50%, plus one."
In a May 2007 press release, see the claims reiterated:
"Instant Runoff voting increases convenience to voters; preserves majority rule by ensuring
winners receive more than 50 percent of the votes; and saves taxpayers and candidates
money by holding only one election."
The results? Don Frantz won with a plurality of votes.
October 9, 2007 Cary District B City Council contest won with 46.36% of all votes cast.
Cary participated in an IRV pilot that year. After running voters 1, 2n and 3rd choices,
Don Frantz obtained 1,401 votes, which is 46.36% of all votes cast in the Cary District B contest.
He was declared the winner after receiving less than 40 percent of the first-choice votes cast,
and less than 50 percent of the votes of people who showed up on Election Day.
COUNCIL MEMBER C-B 1 CARY MUNICIPAL DISTRICT B
Don Frantz . . . . . . . . . . 1,151
Vickie Maxwell. . . . . . . . . 1,075
Nels Roseland . . . . . . . . . 793
WRITE-IN. . . . . . . . . . . 3
The total number of ballots cast in Dictrict B was 3,022.
You can get an engineered majority when you remove Nels Roseland's 793 votes and the 3 write ins.
Here are results only showing vote tallies for top two candidates Frantz and Maxwell
San Francisco, California
San Francisco elections held by IRV (instant runoff) and ordinary top-2-runoff (T2R)
~Warren D. Smith Nov 2009
SF switched to using "bastardized-top-3-only IRV," (which I will abbreviate IRV3)
instead of T2R, holding first IRV3 election in November 2004.
SUMMARY OF IRV ERA: 14 elections looked at. IRV process actually needed (psuedo-runoff) in 7.
Every IRV winner also was a plain-plurality winner. Due to "ballot exhaustion," no IRV winner
(on occasions when the IRV process was actually needed) ever got a majority (i.e. over 50%)
of the eligible ballots, in any round, EXCEPT for Ting in the 2005 Assessor-Recorder race.
SUMMARY OF TOP-2-RUNOFF PRE-IRV ERA: 19 elections looked at. 13 required runoff.
Of the 13 runoffs, 5 changed, and 8 preserved, the plurality winner. Every winner had a majority
of the ballots cast. The voter turnout in the runoff (2nd) round exceeded the turnout in round #1
in the mayor and DA races, but fell below it for the district supervisor races
The majority obtained by the winner of an IRV election is not always a majority
of valid ballots cast, but rather a majority of ballots that indicated a preference
between the runoff finalists. There are two possible reasons for this "majority failure":
First, as in a common plurality or two-election runoff system, there may be a
compromise candidate who is preferred by most voters to the actual winner,
but whose lack of first choice support meant the candidate did not make it
into the final runoff.
Secondly, exhausted ballots, those with no votes on them
for any remaining candidate, can result in the IRV winner not having received a
vote from a majority of voters, but only a majority of votes from remaining ballots.
In an election with many candidates and limited ranking, as with San Francisco
Supervisor elections, exhausted ballots may be common
It's true that runoff elections are being avoided in San Francisco, but the basic cause
of the prior massive need for runoffs was nonpartisan elections with top-two runoff,
thus encouraging large numbers of candidates. If the elections had all been plurality,
the winners would have remained the same, which is remarkable, I did not expect to
see this to be the case so strongly, for IRV, like top-two runoff, will encourage more
candidates to run and will cause the first round vote to be split far more than would
happen with actual plurality elections. If preference voting is going to be used, it would
seem that limiting it to three ranks when there are hordes of candidates creates a problem;
on the other hand, it's not clear how many voters would use additional ranks.
IRV in Australia is being used for partisan elections. One of the selling points of RCV
was to find a majority without holding runoffs; that is not happening, *at all*.
It could be claimed that actual runoffs create a false majority just as much as
do RCV elections (these elections are reported with majority victories based on exclusion
of exhausted ballots); however, with actual runoffs the voters have a chance to make
a choice between the top two; whereas with these elections many voters were excluded
from making that choice, and we don't know how many of them were excluded
because they did not use all the ranks (their fault?) or were excluded because
they *did* use the ranks, but all three were used up.
One thing to be learned from this analysis is a bit of an appreciation of
shortcomings that sometimes actually bite. It usually works.
The above discusion taken from the wikipedia "Discussion" page on Instant Runoff Voting,