The Constitutional Court yesterday ruled that most of the amendments passed by the legislature expanding its power to oversee the executive branch of government are unconstitutional, including those that would have given lawmakers broader investigative powers.

The ruling dealt a blow to opposition Chinese Nationalist Party (KMT) and Taiwan People’s Party (TPP) legislators, who used their combined majority to push through the amendments to the Act Governing the Legislative Yuan’s Power (立法院職權行使法) and the Criminal Code on May 28.

The Constitutional Court found revisions that permit investigative committees in the legislature to request information from officials, military personnel and representatives of public or private entities to be unconstitutional.