Glenn Greenwald - the reporter who broke the story about the National Security Agency's surveillance programs - claimed that those NSA programs allowed even low-level analysts to search the private emails and phone calls of Americans. The NSA has trillions of telephone calls and emails in their databases that they've collected over the last several years," Greenwald told ABC News' George Stephanopoulos. "All an analyst has to do is enter an email address or an IP address, and [the program] searches that database and lets them listen to the calls or read the emails of everything that the NSA has stored, or look at the browsing histories or Google search terms that you've entered." Greenwald explained that ... these programs still allow analysts to search through data with little court approval or supervision. Greenwald said "these systems allow analysts to listen to whatever emails they want, whatever telephone calls, browsing histories, Microsoft Word documents. And it's all done with no need to go to a court, with no need to even get supervisor approval on the part of the analyst," he added. Greenwald said the existence of these analyst search programs are in line with the claims of Edward Snowden, who first leaked details of the NSA's surveillance programs last month. "It's an incredibly powerful and invasive tool, exactly of the type that Mr. Snowden described," Greenwald said. "NSA officials are going to be testifying before the Senate on Wednesday, and I defy them to deny that these programs work exactly as I just said," Greenwald said.