Japan’s Centrist Reform Alliance Is Latest Entity to Emerge from Tangled History of Opposition Realignments

The Yomiuri Shimbun

21:00 JST, January 23, 2026

Japan’s opposition political forces have repeatedly formed new parties or merged with each other over the past 30 years in their efforts to counter the long-dominant Liberal Democratic Party. The creation this month of the Centrist Reform Alliance via a tie-up between the opposition Constitutional Democratic Party of Japan (CDPJ) and Komeito — which until recently had been the LDP’s ruling coalition partner — is only the latest example.

The CDPJ traces its lineage to the former Democratic Party of Japan (DPJ), which was established in 1996 with lawmakers mainly from the Social Democratic Party and New Party Sakigake.

In 1998, the DPJ, together Minseito (Good Governance Party) and others united to launch a new party — which also adopted the Democratic Party of Japan name. This marked the start of significant moves toward what turned out to be a short-lived two-party system.

In 2003, the new DPJ merged with the Liberal Party led by politician Ichiro Ozawa and went on to achieve significant gains in the 2007 House of Councilors election. Using the leverage provided by a “twisted Diet” — where the majority in each house differed — it challenged the ruling coalition of the Liberal Democratic Party and what was then called New Komeito.

The DPJ achieved a landslide victory in the 2009 House of Representatives election, forcing the LDP-New Komeito government out of power and bringing about a change of government.

However, the DPJ-led administration failed to deliver on key campaign promises outlined in its manifesto, such as free expressways and child allowances, disappointing the public. After suffering a crushing defeat in the 2012 House of Representatives election, it fell from power after just three years and three months.

When the LDP returned to power under then Prime Minister Shinzo Abe, who derided “the nightmare DPJ administration,” the DPJ’s popularity continued to decline. In 2016, the party merged with the Japan Innovation Party to form the Democratic Party.

In 2017, some lawmakers from the Democratic Party joined the Party of Hope led by Tokyo Gov. Yuriko Koike, while those did not join the party, including Yukio Edano, formed the CDPJ.

Subsequently, Democratic Party members remaining in the House of Councilors merged with the Party of Hope to form the Democratic Party for the People. The CDPJ and the DPFP then merged to form the current CDPJ. The current DPFP consists of lawmakers who did not join the CDPJ.

And this month, over 140 CDPJ members joined the new party, the Centrist Reform Alliance, but the CDPJ itself continues to exist in the House of Councilors.

LDP Secretary General Shunichi Suzuki, criticized the move, saying, “There is no doubt they formed the party only for the election.”