This week, the Elections Bill was amended to replace the Supplementary Vote (SV) system used for electing mayors and police and crime commissioners (PCCs) in England and Wales with First Past the Post (FPTP). But, as Alan Renwick and Alejandro Castillo-Powell argue, the arguments put forth by ministers are not as convincing as they might at first appear.

Ministers plan to replace the Supplementary Vote (SV) system used for electing mayors and police and crime commissioners (PCCs) in England and Wales with First Past the Post (FPTP). The most detailed explanation for the change given so far appeared in a press release last month, which gave five arguments for the switch: (1) SV increases the number of spoilt ballots; (2) it allows ‘loser’ candidates to win; (3) FPTP improves accountability by ‘making it easier for voters to express a clear choice’; (4) FPTP ‘is the world’s most widely used electoral system’; and (5) SV is ‘an anomaly’ and ‘out of step with other elections in England’. In the written statement that first trailed the proposals, Home Secretary Priti Patel also said (6) that the change ‘reflects that transferable voting systems were rejected by the British people in the 2011 nationwide referendum’. Some of these arguments were repeated, though in less detail, when the matter was considered at the Committee Stage of the Commons bill’s scrutiny earlier this week.

This post assesses the government’s claims in turn. Some have merit, but important counterarguments are ignored. Voting systems should be treated with care: it is all too easy for those in power to manipulate them to their own advantage. Ministers have not adequately made the case that the change will be good for democracy.

1. Does Supplementary Vote lead to more spoilt ballots

Elections using SV in the UK typically see higher numbers of spoilt ballots than do those using FPTP. Electoral Commission data shows that 0.8% of ballots cast in local council elections in May – under FPTP – were rejected. That compares to over 2% in most elections under SV. In PCC elections, they stood at 2.9% this year, down from 3.4% in 2016. In London mayoral elections, they have ranged between 1.8% in 2012 and 4.3% this year. They have generally been around 2% in other combined authority mayoral elections, peaking at 2.2% in 2018.

That SV elections show higher rates of rejected ballots does not mean that SV itself is necessarily the culprit. The jump in such ballots in this year’s London mayoral election points to another factor: ballot paper design. The Electoral Commission notes the use in that contest of a new, untested design, split over two columns because of the large number of candidates, which voters described as ‘being confusing/complex’. Poor design similarly led to more spoilt ballots in the 2007 Scottish local and parliamentary elections. Another factor may be deliberate spoiling of ballot papers: the Electoral Commission noted anecdotal evidence of this in the 2012 PCC elections.

So SV elections do see more spoilt ballots than FPTP elections, but improved ballot paper design – and clearer guidance for voters – might ameliorate the problem.