Transparency and civil liberties advocates are warning that the National Security Agency is quietly putting in place mechanisms for American law enforcement agencies to circumvent constitutional protections in criminal investigations.

In a letter to Defense Intelligence Agency head James Clapper, the groups said the NSA is making policy changes that “would fatally weaken existing restrictions on access to the phone calls, emails, and other data the NSA collects.”

Their contention is over NSA’s decision to hand outside law enforcement agencies the keys to its massive trove of information on the activities of American citizens.

The New York Times reported earlier this year:

The change would relax longstanding restrictions on access to the contents of the phone calls and email the security agency vacuums up around the world, including bulk collection of satellite transmissions, communications between foreigners as they cross network switches in the United States, and messages acquired overseas or provided by allies. The idea is to let more experts across American intelligence gain direct access to unprocessed information, increasing the chances that they will recognize any possible nuggets of value. That also means more officials will be looking at private messages — not only foreigners’ phone calls and emails that have not yet had irrelevant personal information screened out, but also communications to, from, or about Americans that the N.S.A.’s foreign intelligence programs swept in incidentally.

Upon hearing reports of the change, a bipartisan duo of lawmakers, Reps. Ted Lieu (D-Calif.) and Blake Farenthold (R-Texas), demanded answers to serious questions about its constitutionality.

“If media accounts are true, this radical policy shift by the NSA would be unconstitutional, and dangerous,” they wrote to the NSA. “The proposed shift in the relationship between our intelligence agencies and the American people should not be done in secret.

“NSA’s mission has never been, and should never be, domestic policing or domestic spying.”

The change could basically hand over to law enforcement agencies data gathered by the NSA under the authority of Executive Order 12333, which the NSA has used to justify bulk gathering of telephone conversations and the contents of email accounts in the past.

A coalition of 33 civil liberties organizations outlined their concerns in a letter to the NSA Thursday, writing:

Currently … [law enforcement] access to raw data containing U.S. persons’ identities is limited. Intelligence reports disseminated to other agencies may include U.S. persons’ identities only if the U.S. person has consented, the information is publicly available, or the identity of the U.S. person is necessary to understand the foreign intelligence information or assess its importance. The reported changes would jettison these longstanding restrictions and allow multiple other government agencies access to the NSA’s raw take. This change is particularly troubling because EO 12333 data collection is far broader than the controversial surveillance programs carried out under the auspices of other legal authorities, such as Section 702 of the Foreign Intelligence Surveillance Act (FISA). Data obtained under EO 12333 may be gathered through mass, even indiscriminate, surveillance. Given that even wholly domestic communications today may be routed or stored overseas, such broad surveillance inevitably captures the data of millions of Americans. Sharing such information with U.S. law enforcement agencies would allow them to circumvent the strict, constitutionally mandated rules of evidence gathering that govern ordinary criminal investigations.

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