WASHINGTON — Kentucky Sen. Rand Paul said the Department of Justice should have sought a warrant from a judge to obtain The Associated Press’s phone records, suggesting that it is a slippery slope if the DOJ is allowed to unilaterally make the determination about whether obtaining certain information is necessary to protect national security.

“The First Amendment protection of the speech should be significantly protected, and that means you should have a judge’s warrant before you get any records,” Paul said Tuesday. “I don’t like the idea of using subpoenas for something like that.”

The Associated Press reported Monday that the Justice Department had obtained phone records for reporters and editors for a two-month period last year without notifying the AP. During that period, the AP reported on a CIA operation in Yemen to prevent an airline bomb plot. The Justice Department had previously said it was looking into the source of the leak that gave the AP that story.

Attorney General Eric Holder said earlier on Tuesday that the leak was “very, very serious,” and “put the American people at risk.”

Still, Paul said, if it’s legitimately a question of national security, then the department should be able to convince a judge to give them a warrant.

“If we allow the government, any government, to make those decisions willy nilly without a judge ruling on this, they’ll always say everything’s in our national security interest,” he said.

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