U.S. Sen. Al Franken said Monday that he is not surprised by the existence of National Security Agency data-gathering programs that were publicly disclosed last week.

As a member of the Senate Judiciary Committee, Franken said he was briefed on those programs before they became public.

"I availed myself of these briefings, so nothing surprised me," he said Monday while at an event in Falcon Heights. The Minnesota Democrat said he was aware of "the architecture of these programs" because of those briefings.

Late last week, through disclosures by the media, Americans learned NSA has gathered information from Internet and cellphone servers. According to various reports, the agency gathered data from Microsoft, Yahoo, Google, Facebook, Skype, YouTube and Verizon.

When news of the leak was first reported, Franken's office was vague about what he knew about the program. By Saturday, when parts of the program were immediately declassified, Franken become more specific about his knowledge.

Sen. Amy Klobuchar, D-Minn. on Monday acknowledged, in a statement released by her staff, that she too had been briefed on the programs. Like Franken, Klobuchar is on the Judiciary Committee. Her office said Monday that she was not available for an interview.

When first asked about the programs, Franken released a statement through his staff last week saying that, "The American public can't be kept in the dark about the basic architecture of the programs designed to protect them."

On Monday, Franken said: "I think there should be enough transparency that the American people understand what is happening. … But I can assure you that this isn't about spying on the American people."

Franken, who leads the Judiciary's subcommittee on Privacy, Technology and the Law, said there are aspects of security programs that he needs to be aware of, but that should be shielded from public view.

"There are certain things that are appropriate for me to know that (are) not appropriate for the bad guys to know," Franken said Monday. "Anything that, quote, the American people know, the bad guys know, so there's a line here, right? And there's a balance that has to be struck between the responsibility of the federal government to protect the American people and then people's right to privacy. We have safeguards in place … The American people can't know everything because everything they know, then the bad guys will know."

He said that the data the security agency has collected have kept Americans safe.

"I have a high level of confidence, that it is used … to protect us and I know that it has been successful in preventing terrorism," he said.

Franken, who is running for re-election, said he is not confident that the proper balance has been struck between privacy and safety concerns. "We haven't quite hit the exact balance we want to," he said. "I have been for more transparency and I actually co-sponsored legislation to require the FISA court to release their opinions on why they've decided the way they have."

Staff writer Corey Mitchell contributed to this report.

Rachel E. Stassen-Berger • Twitter: @rachelsb