The National Rifle Association filed an amicus brief on Wednesday supporting the American Civil Liberties Union’s lawsuit challenging the constitutionality of the National Security Agency’s phone records collection program.

The NRA filed a brief of amicus curiae in U.S. District Court in support of the plaintiff in the ACLU’s lawsuit against key Obama administration officials, including director of national intelligence James Clapper, NSA director Keith Alexander, defense secretary Chuck Hagel, Attorney General Eric Holder and FBI director Robert Mueller.

The gun-rights group — often associated in the public consciousness with conservative politics — and the progressive-leaning civil rights advocacy organization might appear to be strange bedfellows, but the NRA claims that the two groups have common interests.

“The mass surveillance program threatens the First Amendment rights of the NRA and its members,” according to the NRA counsel’s argument in the amicus brief. “The mass surveillance program could allow identification of NRA members, supporters, potential members, and other persons with whom the NRA communicates, potentially chilling their willingness to communicate with the NRA.”

“If programs like those currently justified by the government’s interpretation are allowed to continue and grow unchecked, they could also contrary to clear congressional intent undo decades of legal protection for the privacy of Americans in general, and of gun owners in particular,” according to the NRA counsel’s conclusion.

The ACLU filed its lawsuit in June, following public revelations regarding what it called “the NSA’s unprecedented mass surveillance of phone calls.”

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