law enforcement powers or internal security functions." members of the congress is legal experts interpreted that language as a clear prohibition against any internal security function under any circumstanc circumstances. a group of c.i.a. officials have a different interpretation. they decided that the 1947 law contained legal gray areas that allowed the c.i.a. to monitor american citizens for possible contact with foreign agents. they believed this meant that they could secretly tap americans' phones, open their mail and plint listening devices in their -- and plant listening devices in their homes, among other things. this secret legal interpretation led the c.i.a. to maintain intelligence files on more than 10,000 american citizens, including reporters, members of congress, and a host of antiwar activists. this small group of c.i.a. officials kept the program and their -- quote -- "gray area justification" of the program a secret from the american people and most of the government because, they argued, revealing it would violate the agency's responsibility to protect intelligence sources and methods from unauthorized disclosure. did th