The Constitutional Court ruled that the so-called "blockade clause" in the Public Official Election Act, which allocates proportional representation seats only to parties that win at least 3% of the vote in the proportional representation ballot conducted separately from constituency votes in general elections, is unconstitutional.
On the 29th, the Constitutional Court, in a constitutional complaint filed by the Labor Party, Mirae Party, The Progressive Party, Green Party Korea, and the Korea Association of Small Merchants Party, ruled unconstitutional by a 7-2 vote of the justices on Article 189, Paragraph 1 of the Public Official Election Act, the clause blocking the allocation of proportional representative National Assembly seats.
Article 189, Paragraph 1 of the election law limits the parties that can be allocated proportional representative National Assembly seats based on general election results. A party must either "win at least 3% of the total valid votes nationwide in the proportional representative National Assembly election" or "win at least five constituency National Assembly seats" to receive proportional seats. Accordingly, as a rule, a party must exceed 3% in the proportional vote to gain proportional seats.
The Labor Party and others who filed the constitutional review argued that the "blockade clause" in the Public Official Election Act "can increase wasted votes and distort the public will," and that "candidates of new parties are not fairly represented and thus have their right to hold public office infringed."
The Constitutional Court said of the blockade clause that "it has institutional utility when the harms of a proliferation of minor parties are serious," but also that "it has the negative effect of blocking new political forces from entering the legislature."
The Constitutional Court noted that in Korea's political system, a two-party system centered on two major parties has long been entrenched, and that proportional representatives number only 46 out of 300 lawmakers (15.3%), which is few. It also viewed that, because the government is a presidential system, the ruling party has less need to form a majority within the legislature.
The Constitutional Court said, "If we assume the abolition of the threshold clause (blockade clause) and recalculate the allocation of proportional seats in the 22nd general election, some parties that failed to elect a member would enter the legislature, but their number would likely be small," adding, "Even if the threshold clause is abolished, the risk that the legislature will be paralyzed by a proliferation of minor parties is not high."
It also pointed out that "constituency elections operate under a single-member district, first-past-the-post system, which already favors major parties," and that "the Public Official Election Act adds a threshold clause, setting a double barrier to entry for minor parties." It concluded, "The threshold clause induces voters to avoid voting for minor parties, depriving them of the opportunity to grow into entering the legislature."
Justices Jeong Hyeong-sik and Cho Han-chang dissented. The two justices said, "Parties must be able to translate the people's will into policy or legislation, so only parties with political capacity need to participate in the composition of the legislature," adding, "Discriminating among parties in seat allocation can be permissible."
They continued, "Today, extremist forces rally supporters faster than centrist parties by provoking anger and anxiety about society with simple and powerful messages," and said, "If extremist forces supported only by a very small minority enter the legislature, their activities could be greatly emboldened, and there is a risk they will disrupt parliamentary politics and stoke social conflict."
Justices Kim Sang-hwan and Jeong Jeong-mi issued concurring opinions. They said, "Even without a threshold clause, to win at least one proportional seat requires roughly a 1%–2% share of the vote, about 280,000–560,000 votes," adding, "That in itself functions as a natural threshold clause."
In the general election held in Apr. 2024, only the Democratic Coalition for Democracy, the satellite party of the Democratic Party of Korea (26.69% of the vote), People's Future, the satellite party of the People Power Party (36.67%), the Rebuilding Korea Party (24.25%), and the Reform Party (3.61%) exceeded 3% and received proportional seats. The Liberty Unification Party (2.26%), the Green Justice Party (2.14%), and New Future (1.70%) did not receive any seats.