Complex sentence: The committee (also called the Special Group) included the CIA director, the national security adviser, and the deputy secretaries at State and Defence and had the responsibility to decide whether covert actions were "proper" and in the national interest.
Split into simpler sentences: The committee (also called the Special Group) included the CIA director, the national security adviser, and the deputy secretaries at State and Defense. They were to determine whether covert actions were "proper" and in the national interest.