Exemple de fonctionnement du scrutin à membre additionné

Allocating Seats on the Regional List

1. In each region, the number of votes cast for each party in the “second vote” for a regional list is totalled.

2. This total is then divided by the figure which equals one plus the number of constituency members elected for that party in that region.

3. The first regional seat is then allocated to the political party, or a candidate standing as an individual, having the highest figure after the calculation in step 2 above has been carried out.

4. The total votes cast for each party in the region are then divided by the figure which equals one plus the number of constituency and regional members elected for that party in that region.

5. The next regional seat is then allocated tot eh political party, or candidate standing as an individual , now having the highest figure after the calculation in step 4 above has been carried out.

6. This process of recalculation of the figure for each party is then carried out until all the places for regional members have been allocated.

7. Seats on the regional list are allocated to candidates in the order in which the political parties have placed them on the list prior to the election.

The following example shows how the system of allocation of seats for votes is carried out (this example assumes that there are seven regional seats to be allocated).

1. Assume that in a particular region, the number of individual constituency members elected for each party is as follows: Labour 6; SNP 1; Conservative 1; Liberal Democrat 1.

2. Assume also that in that region, the number of votes cast for the “second” regional ballot is as follows:

Labour 150,000

SNP 110,000

Conservative 50,000

Liberal Democrat 40,000

Green 30,000

Scottish Socialist 10,000

Independent 10,000

3. The above totals are then divided by the figure equalling one plus the number of constituency members elected for each party. That figure is Labour 7; SNP 2; Conservative 2; Liberal Democrat 2. That gives the following figures:

Labour 21,429 (150,000 divided by 7)

SNP 55,000 (110,000 divided by 2)

Conservative 25,000 (50,000 divided by 2)

Liberal Democrat 20,000 (40,000 divided by 2)

Green 30,000

Independent 10,000

Scottish Socialist 10,000

As a result of this calculation, the SNP now has the highest figure, so the top person on its regional list is elected. At this point, the total number of MSPs elected for each party is as follows: Labour 6; SNP 2; Conservative 1; Liberal Democrat 1.

4. The votes cast for each party are now recalculated by dividing them with the total of seats won for both constituency and regional members. That gives the following figures:

Labour 21,429 (150,000 divided by 7)

SNP 33,333 (110,000 divided by 3)

Conservative 25,000 (50,000 divided by 2)

Liberal Democrat 20,000 (40,000 divided by 2)

Green 30,000

Independent 10,000

Scottish Socialist 10,000

The figure for the SNP is still higher than the figure for any other party, so the second person on the SNP’s regional list is now elected. At this point, the total number of MSPs elected for each party is as follows: Labour 6; SNP 3; Conservative 1; Liberal Democrat 1.

5. The votes cast for each party are now recalculated again. That gives the following figures:

Labour 21,429 (150,000 divided by 7)

SNP 27,500 (110,000 divided by 4)

Conservative 25,000 (50,000 divided by 2)

Liberal Democrat 20,000 (40,000 divided by 2)

Green 30,000

Independent 10,000

Scottish Socialist 10,000

The party list which now has the highest number of votes is the Green party, which therefore has the top candidate on their regional list elected. At this point, the total number of MSPs elected for each party is as follows: Labour 6; SNP 3; Conservative 1; Liberal Democrat 1; Green 1.

6. The votes cast for each party are now recalculated again. That gives the following figures:

Labour 21,429 (150,000 divided by 7)

SNP 27,500 (110,000 divided by 4)

Conservative 25,000 (50,000 divided by 2)

Liberal Democrat 20,000 (40,000 divided by 2)

Green 15,000 (30,000 divided by 2)

Independent 10,000

Scottish Socialist 10,000

The SNP now has the highest figure, so the third person on its regional list is now elected. At this point, the total number of MSPs elected for each party is as follows: Labour 6; SNP 4; Conservative 1; Liberal Democrat 1; Green 1.

7. The votes cast for each party are now recalculated again. That gives the following figures:

Labour 21,429 (150,000 divided by 7)

SNP 22,000 (110,000 divided by 5)

Conservative 25,000 (50,000 divided by 2)

Liberal Democrat 20,000 (40,000 divided by 2)

Green 15,000 (30,000 divided by 2)

Independent 10,000

Scottish Socialist 10,000

The Conservatives now have the highest figure, so the top person on their regional list is elected. At this point, the total number of MSPs elected for each party is as follows: Labour 6; SNP 4; Conservative 2; Liberal Democrat 1; Green 1.

8. The votes cast for each party are now recalculated again. That gives the following figures:

Labour 21,429 (150,000 divided by 7)

SNP 22,000 (110,000 divided by 5)

Conservative 16,666 (50,000 divided by 3)

Liberal Democrat 20,000 (40,000 divided by 2)

Green 15,000 (30,000 divided by 2)

Independent 10,000

Scottish Socialist 10,000

The SNP now has the highest figure, so the fourth person on its regional list is now elected. At this point, the total number of MSPs elected for each party is as follows: Labour 6; SNP 5; Conservative 2; Liberal Democrat 1; Green 1.

9. The votes cast for each party are now recalculated again. That gives the following figures:

Labour 21,429 (150,000 divided by 7)

SNP 18,333 (110,000 divided by 6)

Conservative 16,666 (50,000 divided by 3)

Liberal Democrat 20,000 (40,000 divided by 2)

Green 15,000 (30,000 divided by 2)

Independent 10,000

Scottish Socialist 10,000

Labour now has the highest figure, so the top person on their regional list is elected. At this point, the total number of MSPs elected for each party is as follows: Labour 7; SNP 5; Conservative 2; Liberal Democrat 1; Green 1.

The number of seats won as both constituency and regional members can then be contrasted with the number of votes cast for each regional list, as shown in the following table:

Source : Jean McFadden et Mark Lazarowicz, The Scottish Parliament, An Introduction, T & T Clark, 1999, p. 26-28