Designating an entire mosque as a terrorism enterprise means that anyone who attends prayer services there is a potential subject of an investigation and fair game for surveillance.
Many TEIs stretch for years, allowing surveillance to continue even though the NYPD has never criminally charged a mosque or Islamic organization with operating as a terrorism enterprise.
The documents show in detail how, in its hunt for terrorists, the NYPD investigated countless innocent New York Muslims and put information about them in secret police files. As a tactic, opening an enterprise investigation on a mosque is so potentially invasive that while the NYPD conducted at least a dozen, the FBI never did one, according to interviews with federal law enforcement officials.
De Blasio said Wednesday on Twitter that he was "deeply troubled NYPD has labelled entire mosques & Muslim orgs terror groups with seemingly no leads. Security AND liberty make us strong."