"The government will not state clearly what the rules are with respect to tracking Americans on their cellphones, and I have asked this repeatedly at public hearings in the Intelligence Committee," the Oregon Democrat and member of the Senate Intelligence Committee told the C-SPAN program "Newsmakers."
"I can't get into the details of any specific operation, or whether it's being conducted, but ... having that computer in your pocket increases the potential that certainly people could be tracked 24/7," he told the program, which aired Sunday.
"Under the Patriot Act, the government's authority to collect is essentially limitless."
The U.S. Foreign Intelligence Surveillance Court, which decides how intrusive the government can be in the name of national security, must be overhauled, he said. The court has expanded its powers beyond what Congress envisioned in establishing it in the 1978 Foreign Intelligence Surveillance Act -- yet many court processes remain the same as they were 35 years ago.
"I think, in many particulars, the FISA Court is just anachronistic," he said. "They're using processes that simply don't fit the times.
"When the FISA Act was passed in the '70s, nobody envisioned, for example, some of the astounding reach that the court has gone to with respect to the Patriot Act. And in its definition of 'relevance,' the statute talks about relevance and nowhere does it even suggest that you could collect the phone records of millions and millions of law-abiding Americans."
The New York Times reported Monday the movement afoot in Congress to rein in the NSA has gained a decidedly bipartisan flavor, with Reps. Jim Sensenbrenner, R-Wis., and Zoe Lofgren, D-Calif., starting to formulate legislation in the House Judiciary Committee.
"There is a growing sense that things have really gone a-kilter here," Lofgren said.
Sensenbrenner said Friday he would have a bill ready by the time lawmakers finish their August vacation, the Times said. He said the legislation would place restrictions on who can be targeted for surveillance, give companies permission to reveal their dealings before the secret court that monitors the surveillance and make changes to the court itself, the newspaper said.
"We're talking through it right now," Chambliss told the Times. "There are a lot of ideas on the table, and it's pretty obvious that we've got some uneasy folks."
Wyden said he would likely support legislative proposals to overhaul the secretive court.
He said he supported a bill introduced by Rep. Adam Schiff, D-Calif., which would give the president the power to nominate judges for the court, subject to Senate approval.
The existing law gives that power to the chief justice of the United States, currently John Roberts, whose decisions are final.
Roberts has chosen 10 of the court's 11 judges.
The New York Times reported Friday Roberts, more than his predecessors, has chosen judges with conservative and executive branch backgrounds. Critics say these backgrounds make the court more likely to defer to government arguments domestic spying programs are necessary.
"It's the most one-sided legal process in the United States. I don't know of any other legal system or court that really doesn't highlight anything except one point of view," Wyden said.
"When that point of view -- the executive point of view -- essentially dominates the thinking of the new judges, you've got a fairly combustible situation on your hands," he said.
But House Intelligence Committee Chairman Mike Rogers, R-Mich., told NBC's "Meet the Press" the U.S. National Security Agency doesn't spy on Americans.
People reveal more information about themselves when they mail a letter than what the U.S. National Security Agency collects with its surveillance, he said.
"In this program, zero privacy violations, 54 violent terrorist attacks thwarted. That's a pretty good record. That's a great record," he said. "And that tells me this is one program that works to protect your privacy and live up to our constitutional obligation in Congress that says we must provide for the general defense of the United States."
He said when a suspected terrorist's phone number shows up in the NSA's dragnet domestic surveillance, "what we do about it is say, oops, that's bad. We're going to give this to the FBI to determine who that person even is. And so that's the way we protect their privacy. And that's why there's been zero privacy violations with this. And it's been able to be used to stop 54 violent terrorist acts."