To follow up even the Supreme Court ruled in 1928 that a wiretap did not constitute a search under the 4th Amendment so there was no need for a warrant. Wireta

To follow up even the Supreme Court ruled in 1928 that a wiretap did not constitute a search under the 4th Amendment so there was no need for a warrant. Wiretaps themselves became illegal and the information from them inadmissible under the 1934 Communications Act. This didn't really stop wiretaps. Instead they were used as a method of intelligence gathering to go and find stuff that was admissible. Note that this was not a reflection on the Constitutionality of wiretaps, but instead the sense that they just weren't needed to convict criminals. By the 1960's wiretaps were again brought to the Supreme Court and they outlined how a wiretap statue could pass Constitutional muster. The Katz case is where the "expectation of privacy" language was introduced. This resulted in wiretap statues passing in late the late 60s and that's basically what we had until the PATRIOT Act of 2001. http://www.americanbar.org/content/dam/aba/administrative/litigation/materials/sac_2012/29-1_history_and_law_of_wiretapping.authcheckdam.pdf http://www.americanbar.org/content/dam/aba/administrative/li...