The New York Police Department has labeled certain mosques as terrorist organizations, allowing police to keep an eye on worshipers and imams who might be involved in terrorist activity.

Since the September 11, 2001 attacks, the NYPD has opened at least a dozen "terrorism enterprise investigations" (TEIs) as part of an initiative to help police infiltrate and investigate secret terrorist cells.

Information about the TEIs were revealed by Associated Press after the news organization recently saw a number of documents on the subject. The TEIs are also part of a new book, "Enemies within: inside the NYPD’s Secret Spying Unit and Bin Laden’s Final Plot Against America," by AP reporters Matt Apuzzo and Adam Goldman, as well as interviews with current and former NYPD, FBI and CIA officials.

Before the NYPD could target mosques for surveillance, the procedure had to be approved by a federal judge who established guidelines on how police can conduct surveillance on citizens.

David Cohen, a former CIA executive who became the NYPD deputy commissioner for intelligence in 2002, told the judge deciding the case that mosques could be used "to shield the work of terrorists from law enforcement scrutiny by taking advantage of restrictions of the investigation of First Amendment activity."

The recent revelations of the NYPD’s investigation have outraged some, including the American Civil Liberties Union (ACLU) who says that mosque programs are unconstitutional.

Yet, as the Clarion Project reported, the ACLU has a history of fiercely fighting against essential U.S. counter-terrorism programs and actions, possible due to the background of one top ACLU official, Jameel Jaffer .  (Interestingly, the ACLU chose not to protect the right of freedom of expression when the White House tried to pressure YouTube to take down the film Innocence of Muslims, a provocative presentation of Mohammed's life, which provoked worldwide riots.)

NYPD police commissioner Raymond Kelly and Mayor Michael Bloomberg have denied that TEI is unconstitutional and insist they are following leads.

"Undercover officers and confidential informants do not enter a mosque unless they are following up on a lead. We have a responsibility to protect New Yorkers from violent crime or another terrorist attack, and we uphold the law in doing so," Kelly said.

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