Behind every prosecution stood the archive. For six decades the insular police's intelligence division, in partnership with the FBI, maintained carpetas — dossiers — on independence supporters: some 135,000 people ultimately had files, built by neighbors, coworkers, and informers, used to deny jobs, licenses, and peace to anyone touched by independentismo. The Cerro Maravilla killings of 1978, in which police executed two young independentistas delivered by an agent provocateur, showed the machinery's lethal end.

In 1988 the Puerto Rico Supreme Court declared the system unconstitutional and ordered the files delivered to their subjects — hundreds of thousands of pages that documented, in the state's own hand, the criminalization of a political ideal. The carpetas' release, and the FBI's parallel disclosure of over 1.8 million pages after 2000, made Puerto Rico the best-documented case of political policing in American history.