A newly declassified opinion from the United States' Foreign Intelligence Surveillance Court says that National Security Agency orders to companies such as Verizon, T-Mobile US, AT&T and Sprint to turn over bulk telephone records does not violate the Constitution's Fourth Amendment. The court also said that none of the companies that have received the orders have challenged the directives.

The opinion by court Judge Claire Eagan, made public Tuesday, spells out her reasons for reauthorizing the phone records collection "of specified telephone service providers" for three months.

The collection program, which the government says is authorized under Section 215 of the Patriot Act, was disclosed by former National Security Agency systems analyst Edward Snowden, provoking a heated debate over civil liberties.

Eagan had asked that her Aug. 29 opinion be declassified "because of the public interest in this matter." On Tuesday, the presiding judge of the FISA Court, U.S. District Judge Reggie Walton, ordered that the opinion be published. Portions of the opinion were blacked out.

"To date, no holder of records who has received an order to produce bulk telephone metadata has challenged the legality of such an order," wrote Eagan, who also serves on the U.S. District Court for the Northern District of Oklahoma, to which she was appointed by President George W. Bush.

She wrote that under Section 215 Congress provided for judicial review of FISA Court orders -- first to the FISA Court of Review and, ultimately, to the U.S. Supreme Court. That provides for a "substantial and engaging adversarial process to test the legality of this court's orders under Section 215."

Eagan also concluded that the collection of phone records does not violate the Constitution's Fourth Amendment, which prohibits unreasonable search and seizure.