TAIPEI (Taiwan News) — The KMT legislative caucus said Saturday it will file criminal complaints against five grand justices of Taiwan’s Constitutional Court, accusing them of abuse of power following a ruling to nullify amendments to the Constitutional Court Procedure Act.

In a statement, the caucus said it will lodge complaints with the Taipei District Court and the Taipei District Prosecutors Office, alleging abuse of power, dereliction of duty and violations of Article 124 of the Criminal Code, per CNA.

The move follows a Constitutional Court ruling on Friday that declared unconstitutional amendments to the Constitutional Court Procedure Act passed by the legislature on Dec. 20, 2024. The amendments would have required the support of at least nine justices, from a minimum quorum of 10, for the court to invalidate a law.

The KMT said it was angered by the ruling, arguing that the court overstepped its authority. The Constitutional Court currently has only eight justices in office on its 15-seat bench, as opposition lawmakers have refused to approve nominees put forward by President Lai Ching-te (賴清德).

Three of the eight sitting justices issued dissenting opinions and were not counted among the justices who supported the ruling, according to the court’s decision.

In their majority opinion, the five grand justices said the legislative process behind the amendments had “obvious and significant defects,” violated due process and breached the constitutional principle of separation of powers. As a result, they said the amendments should be deemed null and void from the date of the ruling’s announcement.

The caucus said it will also propose a motion during the next legislative session to condemn the five justices: Shieh Ming-yan (謝銘洋), Lu Tai-lang (呂太郎), Tsai Tzung-jen (蔡宗珍), Chen Chung-wu (陳忠五), and Yu Po-hsiang (尤伯祥).

The caucus said the ruling undermines constitutional law and damages public confidence in the judiciary.