The calculation of party-list MPs by Election Commission favours pro-junta parties as it slices down the opposition. Here’s how it works step-by-step. 

A weapon of math destruction is at work in Thailand. The Election Commission of Thailand (ECT) confirmed the election of 149 party-list MPs on 8 May. The calculation favours the junta as it removes the anti-junta bloc’s majority in the House of Representatives.

The calculation is based on the Organic Law on Election of MPs, which, as the Constitutional Court confirmed on the morning of the same day, does not contradict the 2017 Constitution. Due to the ECT’s method of calculation, as many as 26 parties get party-list MP seats. “No reason, because it follows the law,” said Sawang Boonmee, the Deputy Secretary-General of the ECT. 

The Thai people have waited 45 days for the official election results. It turns out while it takes around 70,000 votes for each seat that the big parties get, it takes as few as 33,754 votes (0.09 percent of the total votes) for the smallest party (e.g. Thai Rak Tham Party) get one seat in the parliament, while the Pheu Thai party, because of its success in getting constituency MPs elected, gets zero party-list MPs.

Had the result been calculated by the fairer method, such as one which set a minimum threshold for getting a party-list MP (the method used in Germany which uses a similar voting method), party-list MPs would be limited to 16 parties, and the Future Forward Party (FFP) claims it should have earned more 7 seats. “We lost more than 7 parliamentary seats,” the FFP posted on Facebook. “These are representatives of people from ethnic groups, representatives of people interested in education reform, representatives from farmers’ groups, democratic activists, the new generation, and representatives from the people of the northeast. What a shame.”

The anti-junta bloc, consisting of Pheu Thai, Pheu Chart, the FFP, the Thai Liberal Party, the Prachachart Party, the Phalang Puangchon Thai Party, and the New Economics Party, which would, by other methods of calculation, have earned 255 seats out of 500 in the House of Representatives, now has only 245 seats.

The Pheu Thai party released a statement protesting the calculation method, while the FFP said it will file a case with the Constitutional Court whether it was against the constitution. However, some small parties with extremist ideas benefited from the ECT’s calculation method.

For example, Paibul Nititawan of the People Reform Party, which got one seat from its 45,374 votes nationwide, campaigned to invoke the teachings of the Buddha to solve people’s problems. Paibul was a Senator during the Yingluck administration and was an implacable foe of the so-called Thaksin regime.  Under the NCPO he was a member of the Constitution Drafting Committee and of the National Reform Council where he headed the Buddhism reform committee.

Mongkolkit Suksintharanon of the Thai Civilized Party, which got one seat from 60,354 votes, vows to bring back whipping to combat corruption. He is Secretary-General of his own National Anti-Corruption Network, which campaigns selectively and did not, for example, touch the scandal of Prawit’s watches.  Another party founder is notorious social media personality Natchapol Supattana or “Mark Pitbull”.

The junta seeks a House majority by gathering MPs from small parties who have benefitted from the ECT’s calculation method. And they returned the favor on 13 May when 11 small parties announced that they will together support Prayut Chan-o-cha to be the Prime Minister. Damrong Phidej, the leader of Thai Forest Conservation Party (2 MPs), which gained 1 more seat from the junta's calculation method, also announced it will join the government led by the junta. 

Before the election results, the junta was relying on the 250 senators, appointed by the junta, to pick Prayut Chan-o-cha to be the Prime Minister, but it would not be able to pass laws because the anti-junta bloc would still hold a majority in the House. With the help of the small parties and the calculation methods, it is now more likely than ever that Thailand will be ruled by the junta under the disguise of democratic election. However, pro-junta Phalang Pracharat Party still needs support from Bhumjaitai Party (51 MPs), Democrat Party (52 MPs) as well as other undecided parties to secure the majority in the house. 

The consequence is obvious, but what’s obscure is how the calculation works. Weapon of math destruction, from the title of a book on big data algorithms authored by Cathy O’Neil, is an apt term for the calculation method designed by the junta to prolong its status quo. Since we owed the explanation of no-explanation to the international community, here is a step-by-step elaboration of how the calculation works according to the ECT’s announcement.

The weapon of math destruction

1. Total the votes from all parties nationwide. According to the ECT, the result is 35,441,920 votes.

2. Since the election in one constituency is still incomplete due to violations, find the number of total MPs and party-list MPs by: 

         (a) Divide the number of all constituency MPs with official results (349) by the number of all constituencies (350) = 349 ÷ 350 = 0.9971.

         (b) Find the total number of MPs to be reported by the ECT by multiplying the result of (b) by the total number of MPs in parliament (500) = 500 × 0.9971 = 498.5714.

         (c) Find the total number of party-list MPs to be reported by the ECT by subtracting the number of all constituency MPs with official results (349) from the result of (b) rounded down  = 498 – 349 = 149.

3. Allocate the 149 party-list MPs by the following steps:

         (d) Divide the total number of votes from (a) by the total number of MPs to be reported from (b) rounded down = (35,441,920 ÷ 498) = 71,168.5141.

         (e) Find the number of MPs each party ‘should get’ by dividing the total number of votes for each party by (d).

         (f) Find the preliminary number of party-list MPs for each party by subtracting the number of constituency MPs of each party from the number of MPs each party ‘should get’ from (e).  Since Pheu Thai Party won more constituency MPs than the number of MPs it ‘should get’, it receives no party-list MPs.

Table 1: How to calculate the preliminary number of party-list MPs

No.	Political Parties	Total Vote	MPs the party ‘should get’	Constituency MPs	Party-list MPs
1.	Phalang Pracharat Party	8,413,413	118.2182	97	21.2182
2.	Pheu Thai Party	7,881,006	110.7373	136	0.0000
3.	Future Forward Party	6,254,726	87.8861	30	57.8861
4.	Democrat Party	3,957,620	55.6091	33	22.6091
5.	Bhumjaithai Party	3,734,055	52.4678	39	13.4678
6.	Thai Liberal Party	822,240	11.5534	0	11.5535
7.	Chart Thai Pattana Party	783,607	11.0106	6	5.0106
8.	New Economics Party	485,574	6.8229	0	6.8229
9.	Prachachart Party	481,143	6.7606	6	0.7606
10.	Phuea Chart Party	419,121	5.8891	0	5.8891
11.	Action Coalition for Thailand	415,202	5.8341	1	4.8341
12.	Chart Pattana Party	244,770	3.4393	1	2.4393
13.	Thai Local Power Party	212,953	2.9922	0	2.9922
14.	Thai Forest Conservation Party	134,532	1.8903	0	1.8903
15.	Thai People Power Party	79,783	1.1210	0	1.1210
16.	Thai Nation Power Party	73,189	1.0284	0	1.0284
17.	People Progressive Party	68,973	0.9692	0	0.9692
18.	Thai Civilized Party	60,354	0.8480	0	0.8480
19.	Phalang Thai Rak Thai Party	60,298	0.8473	0	0.8473
20.	Thai Teacher Power Party	56,308	0.7912	0	0.7912
21.	Prachaniyom Party	56,215	0.7899	0	0.7899
22.	Prachatham Thai Party	47,787	0.6715	0	0.6715
23.	People Reform Party	45,374	0.6376	0	0.6376
24.	Thai Citizen Power Party	44,961	0.6318	0	0.6318
25.	New Democrat Party	39,260	0.5516	0	0.5516
26.	New Palangdharma Party	34,924	0.4907	0	0.4907
27.	Thairaktham Party	33,754	0.4743	0	0.4743
28.	Phuea Paendin Party	30,936	0.4347	0	0.4347
29.	New Alternative Party	29,219	0.4106	0	0.4106
30.	Paradonraphab Party	29,219	0.3861	0	0.3861
	Other parties	…	…	…	…
	Total	35,441,920	498		174.2629

         (g) If the preliminary number of party-list MPs under (f) totals more than the total number of party-list MPs under (c) (149), then divide the number of party-list MPs of each party by the total preliminary number of party-list MPs under (f) (174.2629) and multiply by the total number of party-list MPs under (c) (149). Distribute the party-list MPs according the results rounded down.

         (h) If after (g), the total number of party-list MPs is less than 149, give one more party-list MP to each party which already has a party-list MP and whose preliminary number of party-list MPs under (f) can be rounded up (contains a fraction of more than 0.5).

         (i) If after (h), the total number of party-list MPs is still less than 149, give one party-list MP to each party, excluding those which have received an extra seat under (h), in order of the size of the fraction of the preliminary number of party-list MPs under (f) until the total number of party-list MPs reaches 149.

Table 2: How to calculate the final number of party-list MPs

No.	Political Parties	Total Vote	MPs the party ‘should get’	Constituency MPs	Preliminary Party-list MPs	Subtracted by  preliminary no. (174.2629) and multiplied by 149	Additional MPs gained from rounding up	Final Party-list MPs
1.	Phalang Pracharat Party	8,413,413	118.2182	97	21.2182	18.1422		18
2.	Pheu Thai Party	7,881,006	110.7373	136	0.0000	0.0000
3.	Future Forward Party	6,254,726	87.8861	30	57.8861	49.4943	1	50
4.	Democrat Party	3,957,620	55.6091	33	22.6091	19.3315		19
5.	Bhumjaithai Party	3,734,055	52.4678	39	13.4678	11.5154	1	12
6.	Thai Liberal Party	822,240	11.5534	0	11.5535	9.8785	1	10
7.	Chart Thai Pattana Party	783,607	11.0106	6	5.0106	4.2842		4
8.	New Economics Party	485,574	6.8229	0	6.8229	5.8338	1	6
9.	Prachachart Party	481,143	6.7606	6	0.7606	0.6503	1	1
10.	Phuea Chart Party	419,121	5.8891	0	5.8891	5.0354		5
11.	Action Coalition for Thailand	415,202	5.8341	1	4.8341	4.1333		4
12.	Chart Pattana Party	244,770	3.4393	1	2.4393	2.0857		2
13.	Thai Local Power Party	212,953	2.9922	0	2.9922	2.5584	1	3
14.	Thai Forest Conservation Party	134,532	1.8903	0	1.8903	1.6163	1	2
15.	Thai People Power Party	79,783	1.1210	0	1.1210	0.9584	1	1
16.	Thai Nation Power Party	73,189	1.0284	0	1.0284	0.8793	1	1
17.	People Progressive Party	68,973	0.9692	0	0.9692	0.8287	1	1
18.	Thai Civilized Party	60,354	0.8480	0	0.8480	0.7251	1	1
19.	Phalang Thai Rak Thai Party	60,298	0.8473	0	0.8473	0.7245	1	1
20.	Thai Teacher Power Party	56,308	0.7912	0	0.7912	0.6765	1	1
21.	Prachaniyom Party	56,215	0.7899	0	0.7899	0.6754	1	1
22.	Prachatham Thai Party	47,787	0.6715	0	0.6715	0.5742	1	1
23.	People Reform Party	45,374	0.6376	0	0.6376	0.5452	1	1
24.	Thai Citizen Power Party	44,961	0.6318	0	0.6318	0.5402	1	1
25.	New Democrat Party	39,260	0.5516	0	0.5516	0.4716	1	1
26.	New Palangdharma Party	34,924	0.4907	0	0.4907	0.4196	1	1
27.	Thairaktham Party	33,754	0.4743	0	0.4743	0.4055	1	1
28.	Phuea Paendin Party	30,936	0.4347	0	0.4347	0.3717	1	1
29.	New Alternative Party	29,219	0.4106	0	0.4106	0.3511	1	1
30.	Paradonraphab Party	29,219	0.3861	0	0.3861	0.3301	1	1
	Other parties	…	…	…	…	…
	Total	35,441,920	498		174.2629			149