FISA Amendments Act of 2008

Foreign Intelligence Surveillance Act of 1978 Amendments Act of 2008 or FISA Amendments Act of 2008 - Amends the Foreign Intelligence Surveillance Act of 1978 (FISA) to authorize the Attorney General (AG) and Director of National Intelligence (DNI) to jointly authorize, for periods up to one year, the targeting (electronic surveillance) of persons located outside the United States in order to acquire foreign intelligence information, under specified limitations and requirements.

Authorizes the AG and DNI to direct an electronic communication service provider to: (1) immediately provide the government with all information, facilities, and assistance necessary to accomplish an acquisition of communications; and (2) maintain under security procedures any records concerning such acquisition.

Requires the AG and DNI, at least every six months, to: (1) assess compliance with required targeting and minimization procedures; and (2) submit assessment results to the Foreign Intelligence Surveillance Court (Court) and the congressional intelligence committees.

States that FISA and the procedures of chapters 119 (Wire and Electronic Communications Interception and Interception of Oral Communications), 121 (Stored Wire and Electronic Communications and Transactional Records Access), and 206 (Pen Registers and Trap and Trace Devices) of the federal criminal code shall be the exclusive means by which electronic surveillance and the interception of domestic wire, oral, or electronic communications may be conducted.

Allows the AG to authorize the emergency employment of electronic surveillance if the AG, among other things: (1) determines that an emergency exists; (2) informs a Court judge of such determination; and (3) applies for a Court order authorizing such surveillance.

Requires the AG, after authorizing the installation and use of a pen register or trap and trace device on an emergency basis, to apply to the Court for an authorization order within seven days (current law requires 48 hours) after the emergency installation and use.

Authorizes the Court to sit en banc when: (1) necessary to secure or maintain uniformity of Court decisions; or (2) the proceeding involves a question of exceptional importance.

Authorizes the acquisition of foreign intelligence information in order to prevent the international proliferation of weapons of mass destruction.

Prohibits: (1) civil actions against a communication service provider, or individual other than such a provider, furnishing surveillance assistance requested from an element of the intelligence community; and (2) a state from conducting investigations, imposing sanctions, or commencing or maintaining a civil action or other proceeding against a provider furnishing requested assistance.