2020 Sri Lankan Parliamentary Election

Variations on Proportional Representation

Some hypothetical scenarios

In Understanding Parliamentary Elections, I explained how Sri Lanka’s Proportional Representation based electoral system works.

In particular, I discussed how our “proportional” system is not quite proportional, because of the following factors:

1. Article 96 of the constitution assigned four seats to each of the nine provinces. These, in turn, were distributed amongst districts by the Delimitation Commission. Since, all provinces (big and small — by voter population) got the same number of seats, the smaller provinces got more seats relative to their size. Even within provinces, allocation of seats was not proportional to the voter population, further exaggerating the asymmetry.
2. A Bonus Seat was allocated to the party getting the most number of seats in a district. The allocation happened if the party coming first got even one vote more than the party coming second.
3. Parties qualified for seats at the Electoral District level, only if they got a minimum of 5% of the valid votes of that district. This 5% rule was often a disadvantage to smaller parties.
4. Finally, differences in turnout meant that total seats a party received were not proportional to total votes. A party that got more votes in a district with higher turnout received relatively fewer seats.

In this article, I present some hypothetical scenarios, on what the seat allocation in the 2020 Sri Lankan Parliamentary Election would have been if the above “disproportionalities” did not exist.

Actual 2020 Result

Let’s begin with the actual 2020 result.

2020, ignoring Article 96

If we ignore Article 96 and assign seats to a district in proportion to their voter population, we get the following allocation.

The new allocation favours bigger districts (like Gampaha) and disfavours smaller ones (like Vanni). With the new allocation, the 2020 result would have looked like this:

Since the SLPP and JJB did relative better in larger districts, especially in the “South”, they gain 4 and 1 (Matara) seats respectively, mostly at the expense of the SJB (-2) and the ITAK (-2).

2020, ignoring Article 96 + the Bonus Seat

When we remove the Bonus Seat privilege for the winning party, the SLPP loses six seats. Mostly to the advantage of the SJB that came “second” in many districts, which gains six seats.

2020, ignoring Article 96 + the Bonus Seat + the 5% Rule

When we relax the 5% rule, the JJB gains four seats (Kalutara, Kandy, Galle and Kurunegala). The UNP also gains two seats (Colombo and Gampaha).

The SLPP loses six seats, and the SJB loses two seats.

2020, with perfect proportionality at the national level

Finally, we look at how seats would have been allocation with “perfect proportionality”. That is, if the seats parties got were exactly (save rounding error) proportional to the votes they received islandwide.

The allocation is very similar to the “2020, ignoring Article 96 + the Bonus Seat + the 5% Rule” with minor changes due to turnout. The SLPP and SJB lose two seats each. The UNP gains two seats, while the JJB and ITAK gain one seat each.

Bonus: 2020, with a 12.5%

The 1978 Constitution that originally defined proportional representation stipulated a 12.5% threshold for parties to qualify for Electoral Districts seats. This was subsequently lowered to 5%, apparently at the request of smaller parties.

In this final “Bonus Scenario” we look at the what 2020 result would have been if we replace the 5% rule with the original 12.5% rule.

The chief loser in this scenario is the JJB, which loses its seats from Colombo and Gampaha.