There are 129 seats in the Scottish Parliament at Holyrood. The most recent election to the Scottish Parliament took place on the 5th of May 2016. The SNP formed a minority government following the election. The current distribution of seats is:
The Presiding Officer Ken Macintosh (shown in black) was elected as a Labour MSP. By convention, the PO gives up their party status to impartially chair the Scottish Parliament. As such, the PO does not normally cast a vote.
Of the three MSPs listed as Independents two of them, Mark McDonald and Derek Mackay, were both elected for the SNP in 2016 but left the party following (unlinked) instances of harassment and inappropriate behaviour. The third is Andy Wightman, who left the Greens on the 18th of December 2020.
The Reform UK MSP is Michelle Ballantyne, who left the Conservatives on the 24th of November, initially sitting as an Independent. On the 11th of January 2021, she was announced as the Scottish leader for Reform UK, and changed her affiliation accordingly.
The Basics and How to Vote
Elections to the Scottish Parliament are conducted via the Additional Member System (AMS). This is a partially proportional system that combines First Past the Post (FPTP) with closed-list proportional representation. Of the 129 seats, 73 seats are elected via FPTP, and 56 are elected from the lists. Although voters have two separate votes, one for FPTP and one for the list, the results are linked.
The overall result in each region should then be roughly proportional to a party’s share of the vote. Due to the size of each region, a party will generally require between 5-6% of the vote in order to win a list seat. A party’s list seats will be allocated to candidates in the order they appear on the list, unless that candidate has already been elected in a constituency. So if a party wins two list seats, the first two candidates on their list will be elected. Once elected, there is no difference between a constituency MSP and a list MSP except the electorate they are responsible to. They have the same responsibilities and role in the Scottish Parliament.
Most voters will be familiar with how the FPTP constituency seats work. This part of the election may be referred to as the “constituency vote” or “first vote”. Scotland is divided into 73 constituencies each containing a roughly equal number of voters. Voters cast their ballot for a single candidate, and the candidate that wins the most votes wins the single seat available.
When used alone, this kind of system is often seen as unfair, as it does not accurately represent the spread of voter opinion. For example, if one party wins 50% of the vote in ten seats, it will win all ten seats. The 50% of voters who did not vote for that party are not accurately represented in parliament.
The list seats are intended to help fix that issue. This part of the election may be referred to as the “list vote” or “second vote”, though the latter should be avoided as it incorrectly implies this to be a second preference. The 73 constituencies used for the constituency vote are put together in groups of between eight and ten constituencies to form 8 regions. Voters cast their ballot for a list of candidates, and each region elects 7 list MSPs, but only after the constituency results for the whole region are finalised.
To calculate the winners of the list seats, the d’Hondt formula is used. In each region, every party’s list vote is divided by one more than the number of seats they have won so far. At the start, that will just be constituency seats, and the party with the highest value wins the first list seat. That is added to the party’s total and a new value is calculated for them, and the second seat goes to the party with the new highest value. This process repeats until all 7 seats have been allocated.
The current boundaries for constituencies (black lines) and regions (colours) of the Scottish Parliament are shown below. I’m still struggling to get a nice interactive version of this map, much to my annoyance! Shetland is enjoying a trip southwards in the graphic, for the sake of visual clarity in the Central Belt. More detailed constituency maps are available here.