Editor's note: Peter Bergen is CNN's national security analyst, a director at the New America Foundation and the author of "Manhunt: The Ten-Year Search for bin Laden -- From 9/11 to Abbottabad." This story is adapted from a New America Foundation policy paper.
(CNN) -- On Friday President Obama will address the nation about the NSA's controversial surveillance programs. He is expected to announce some substantive changes to those programs which collect data about the phone calls of every American.
After the first leaks by former NSA contractor Edward Snowden were published in June, Obama defended the NSA's surveillance programs during a visit to Berlin, saying: "We know of at least 50 threats that have been averted because of this information not just in the United States, but, in some cases, threats here in Germany. So lives have been saved."
Similarly, Gen. Keith Alexander, the director of the NSA, testified before Congress that "the information gathered from these programs provided the U.S. government with critical leads to help prevent over 50 potential terrorist events in more than 20 countries around the world."
Rep. Mike Rogers, R-Michigan, chairman of the House Permanent Select Committee on Intelligence, said on the House floor in July that 54 times the NSA programs "stopped and thwarted terrorist attacks both here and in Europe -- saving real lives."
However, a New America Foundation review of the government's claims about the role that NSA "bulk" surveillance of phone and e-mail communications records has had in keeping the United States safe from terrorism found that these claims are overblown and even misleading.
An in-depth analysis of 225 individuals recruited by al Qaeda or a like-minded group, or inspired by al Qaeda ideology, and charged in the United States with an act of terrorism since 9/11, demonstrated that traditional investigative methods, such as the use of informants, tips from local communities, and targeted intelligence operations, provided the initial impetus for investigations in the majority of cases, while the contribution of NSA's bulk surveillance programs to these cases was minimal.
(Click on the link to go to a database of all these 225 individuals and additional details about them and the government's investigations of these cases. )
The controversial bulk collection of American telephone metadata, which includes the telephone numbers that originate and receive calls, as well as the time of those calls but not their content, under Section 215 of the PATRIOT Act, appears to have played an identifiable role in, at most, 1.8% of these cases.
This finding corrobrated that of the Obama-appointed White House review group who had access to classified materials that concluded in December that "section 215 telephony meta-data was not essential to preventing attacks."
Our study also found that NSA programs involving the surveillance of non-U.S. persons outside of the United States under Section 702 of the FISA Amendments Act played a role in 4.4 percent of the terrorism cases we examined, and NSA surveillance under an unidentified authority played a role in 1.3 percent of cases we examined.
In 27 percent of the cases we reviewed, court records and public reporting do not identify which specific methods initiated the investigation. These cases, involving 62 individuals, may have been initiated by an undercover informant, an undercover officer, a family member tip, other traditional law enforcement methods, CIA- or FBI-generated intelligence, NSA surveillance of some kind, or any number of other methods.
Furthermore, our examination of the role of the database of U.S. citizens' telephone metadata in the single plot the government uses to justify the importance of the program -- that of Basaaly Moalin, a San Diego cabdriver who in 2007 and 2008 provided $8,500 to Al-Shabaab, al Qaeda's affiliate in Somalia -- calls into question the necessity of the Section 215 bulk collection program.
According to the government, the database of American phone metadata allows intelligence authorities to quickly circumvent the traditional burden of proof associated with criminal warrants, thus allowing them to "connect the dots" faster and prevent future 9/11-scale attacks. Yet in the Moalin case, after using the NSA's phone database to link a number in Somalia to Moalin, the FBI waited two months to begin an investigation and wiretap his phone.
This undercuts the government's theory that the database of Americans' telephone metadata is necessary to expedite the investigative process, since it clearly didn't expedite the process in the single case the government uses to extol its virtues.
In sum, the surveillance of American phone metadata has had no discernible impact on preventing acts of terrorism and only the most marginal of impacts on preventing terrorist-related activity, such as fundraising for a terrorist group.
Given that, what should the Obama administration do about the NSA's phone data collection program, which keeps the phone data of all Americans for five years?
President Obama has a number of potential choices. The first is to continue the program as is. Another is to give the phone collection program to some kind of private third party entity, and another is to mandate that the phone companies keep the data.
There are problems with all these approaches.
The status quo is open to legal challenges. Judge Richard J. Leon of the District of Columbia ruled in December that the program likely violates the Constitution. Another federal judge, in New York, ruled in favor of the program a week later, so its legal fate might have to be determined by higher courts.
Giving the data collection program to some kind of government-nominated private third party will likely be seen as just another way for the government to store the data. And the phone companies don't want the costs and headaches of storing five years of data.
There is another approach that should be considered, which is to abandon the bulk phone data collection program entirely and go back to the tried and true approach of having the government get a court order to look at a suspect's phone records, rather than leaving that decision to the discretion of a group of anonymous officials at NSA, as is now the case.
This hardly seems onerous. After all, since 1979 judges have only turned down 0.3% of the requests they have received for warrants involving cases of suspected espionage or terrorism. But such a move would assure Americans that there was some sort of due process going on whenever their phone records are examined by the government. And this seems closer to the spirit of the Fourth Amendment, which guards against "unreasonable searches," than does the present system.
Thanks to David Sterman and Emily Schneider for their research help.
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