Should a police department identify and engage those citizens most likely to be involved with terrorism? Should police understand the historic and current ties of certain communities to militant groups that export violent extremism? The current debate over the New York Police Department's counterterrorism surveillance reflects fundamental disagreements over such issues.
Start with a given: The threat of terrorism is no excuse to run roughshod over civil liberties. The leeway given New York's police in combating terrorism is spelled out in the "Handschu Guidelines," federal court-sanctioned rules in force since 1985 and amended in 2002.
NYPD Commissioner Ray Kelly says he has followed these guidelines to the letter, but since last summer a series of Associated Press articles has accused the NYPD of "wholesale surveillance of places where Muslims eat, shop, work and pray"—spying that ostensibly violates their civil rights. Now U.S. Attorney General Eric Holder has asked the Justice Department to review the NYPD program.
Yet NYPD efforts to engage with and selectively surveil at-risk populations are not only legal but essential. In 2002, Mr. Kelly decided that a "broad base of knowledge" about who lives in the New York area was crucial to preventing terrorism. "It was precisely our failure to understand the context in 1993"—after the first World Trade Center bombing—"that left us vulnerable in 2001," he said. So police tried to determine "how individuals seeking to do harm might communicate or conceal themselves. Where might they go to find resources or evade the law?" Such "geographically-based knowledge" saved "precious time in stopping fast-moving plots," he said last weekend.
Identifying such "hot spots" was legal, appropriate—and no secret: NYPD officials testified publicly before Congress about their work. The Handschu guidelines authorize the police to "visit any place and attend any event that is open to the public" and "conduct online search activity and to access online sites and forums on the same terms . . . as members of the public."
Criminals often share ethnic backgrounds. For police to look for certain criminals among certain ethnic groups is only logical, and it doesn't suggest a belief that all, or even a significant minority, of that group are criminals. Cops look for Cosa Nostra members in Italian communities, for Yakuza criminals among Japanese, for Triad criminals among Chinese. To look for al Qaeda members in Muslim communities is not to disparage such communities. Indeed many Muslims help law enforcement identify such potential threats.
What about the NYPD's six-month surveillance of college campuses in the New York area and the Northeast Corridor, in particular of the Muslim Students Association (MSA), which has come under fire?
In 2006, police had ample cause to fear that chapters of the MSA, founded in the U.S. by the militant Muslim Brotherhood, might unwittingly host terrorists or serve as recruiting grounds. "Some of the most dangerous Western al Qaeda linked or inspired terrorists since 9/11 were radicalized or recruited at universities in Muslim Student Associations," said NYPD Deputy Commissioner Paul Browne.
Anwar al-Awlaki, the former head of al Qaeda in the Arabian Peninsula who was killed in a U.S. drone strike last year, was president of the MSA at Colorado State University. Umar Abdulmutallab, the al Qaeda "underwear" bomber who tried blowing up a jet over Detroit in 2009, headed the MSA at the University College of London.
The NYPD asserts, contrary to Associated Press claims, that it surveilled MSA members only after finding signs of terrorist-related activity in the course of other investigations, not from open sources. Leads from those investigations, Mr. Kelly says, triggered preliminary inquiries and, if needed, full-blown investigations using undercover police.
Another misplaced criticism is that the NYPD received assistance from the CIA, thus blurring the line "between foreign and domestic spying," as the AP put it. The architect of the NYPD's intelligence program was CIA vet David Cohen, and the CIA seconded Larry Sanchez to work with Mr. Cohen after 9/11. But this interaction not only has been widely reported for years—it is precisely the kind of expertise-sharing that the 9/11 Commission so strongly urged.
The CIA is rightly precluded from spying on Americans on U.S. soil, but the 1947 National Security Act (as amended) authorizes it to assist local law enforcement "when lives are endangered." That's not a loophole—it's necessary cooperation as terrorism threatens cities.
Though it's far from perfect, the NYPD should be praised for helping foil 14 terrorist plots targeting New York City, all while protecting our civil liberties.
Mr. Clarke was a national security official in the White House for three presidents. Ms. Miller is a contributing editor at the Manhattan Institute's City Journal and a Fox News commentator. Mr. Eddy, a former director of the White House national security council, has advised the NYPD.