<Tr> <Th_colspan="2"> Major amendments </Th> </Tr> <Tr> <Td_colspan="2"> Communications Assistance for Law Enforcement Act USA PATRIOT Act FISA Amendments Act </Td> </Tr> <P> The Electronic Communications Privacy Act of 1986 (ECPA) was enacted by the United States Congress to extend government restrictions on wire taps from telephone calls to include transmissions of electronic data by computer (18 U.S.C. § 2510 et seq .), added new provisions prohibiting access to stored electronic communications, i.e., the Stored Communications Act (SCA, 18 U.S.C. § 2701 et seq .), and added so - called pen trap provisions that permit the tracing of telephone communications (18 U.S.C. § 3121 et seq .). ECPA was an amendment to Title III of the Omnibus Crime Control and Safe Streets Act of 1968 (the Wiretap Statute), which was primarily designed to prevent unauthorized government access to private electronic communications . The ECPA has been amended by the Communications Assistance for Law Enforcement Act (CALEA) of 1994, the USA PATRIOT Act (2001), the USA PATRIOT reauthorization acts (2006), and the FISA Amendments Act (2008). </P> <P> "Electronic communications" means any transfer of signs, signals, writing, images, sounds, data, or intelligence of any nature transmitted in whole or in part by a wire, radio, electromagnetic, photoelectronic or photooptical system that affects interstate or foreign commerce, but excludes the following: </P>

What is the main purpose of the electronic communications privacy act (ecpa)
find me the text answering this question