Meet the Muslim-American Leaders the FBI and NSA Have Been Spying On - The InterceptThe Intercept:
Government agencies have invoked a host of legal theories over the
years to justify spying on Americans without obtaining individual FISA
warrants. Prior to mid-2008, for example, the NSA could target Americans
when they were located on foreign soil simply by obtaining an
authorization from the attorney general. The NSA also relies on the
so-called “FISA backdoor” to read the emails of Americans communicating with foreign targets without obtaining a warrant, and engages in the bulk collection of “metadata”
from Internet service providers without individual warrants. In other
cases, it can obtain a warrant against an entire organization—and then
monitor the emails of individuals allegedly associated with the group.
While the NSA documents do not prove that the government has been
systematically monitoring the communications of political dissidents,
Jaffer notes that some of the most abusive surveillance practices
carried out by the FBI during the 1960s were arguably legal at a time
when many Americans believed that the groups targeted by Hoover’s
FBI—including anti-government activists on the left and right—posed a
threat to the country.