Legal Principles
Wiretaps are “searches” within the meaning of the 4th Amendment (Katz).
- Telephone users have a legitimate expectation of privacy.
But dialed digits are not protected (Smith).
- They are voluntarily “given” to the phone company.
- People know that the phone company can and does record them, i.e., for billing.
FISA: generally restricted to non-“U.S. persons”.