H. Rept. 113-452 Part 2: USA Freedom Act, Report to Accompany H.R. 3361, Including Cost Estimate of the Congressional Budget Office, May 15, 2014 [open pdf - 550KB]
From Background and Need for Legislation: "Until last year, the existence of a program to collect bulk telephone call detail records, also known as telephone metadata, under Section 215 of the USA PATRIOT [Uniting and Strengthening America by Providing Appropriate Tools Required to Intercept and Obstruct Terrorism] Act was highly classified. The classified nature of the program stemmed from the simple fact that if our adversaries knew of the program and its capabilities, they would change their communications patterns so as to evade surveillance. The Committee has been aware of the bulk telephone metadata program since its inception and reauthorized Section 215 in 2005, 2006, 2010, and 2011 because the program was a lawful and effective counterterrorism tool. [...] However, following the unprecedented and unquantifiably damaging unauthorized disclosures of classified information, the Director of National Intelligence declassified many aspects of the bulk telephone metadata program. The unauthorized disclosure of this program and others caused incalculable damage to U.S. national security, much of which may not become apparent for years. Even so, the disclosures have caused public concern about the program, notwithstanding the care demonstrated by the NSA [National Security Administration] to abide by the law and to protect the constitutional rights of U.S. persons. This public concern led the Committee to consider ways to end the bulk collection of telephone metadata and enhance privacy and civil liberties while preserving as much of the operational effectiveness and flexibility of the program as possible."
H. Rept. 113-452 Part 2; House Report 113-452 Part 2
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