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After leaking information on National Security Agency activities, Edward Snowden has been alternately celebrated as a hero and condemned as a traitor to his country. But, underneath the rhetoric, the core issues at the heart of Snowden's case raise specific concerns for civil rights and transparency groups.

Beatrice Edwards, executive director for the Government Accountability Project, said it's about protecting the constitutional rights of American citizens.

"The Snowden disclosures reveal the extent to which the National Security Agency has been violating the Constitution of the U.S.," she said, pointing out that the NSA's PRISM surveillance program and collection of phone call metadata could be considered "unreasonable searches without probable cause" under the Fourth Amendment.

Edwards' organization represented four NSA whistle-blowers "who made disclosures similar to Snowden's some years ago," so she has an in-depth understanding of the gravity of this situation.

"All were subjected to severe retaliation, and one, Thomas Drake, was prosecuted under the Espionage Act as an enemy of the state," she said.

Mike German, policy counsel for the American Civil Liberties Union, said the revelations highlight the need for a public discussion about the role of surveillance in a democratic society.

"I think the NSA leaks exposed the scope of domestic spying that's taking place and the lack of effective mechanisms for the public to learn about how the government is interpreting its surveillance authorities," he said. "Now that the information is public, we can have a debate about whether such secret spying is compatible with a free society."

For Joe Newman, director of communications for the Project On Government Oversight, the issue is about protecting people who challenge government wrongdoing.

"We believe there's still a glaring need for meaningful protection for whistle-blowers," he said. "Currently, there is no protection for federal contract employees in the intelligence field who want to come forward with information about corruption, waste, and abuses of power."

Edwards explained that while the Whistleblower Protection Enhancement Act of 2012 gives federal employees the right to disclose concerns to the Office of Special Counsel (an independent government agency), Congress "stripped protection for whistle-blowers in national security agencies out of the legislation the OSC enforces." This means whistle-blowers like Snowden have no protection against retaliation.

A Gallup poll released earlier this month showed that a majority of Americans -- 53 percent -- share these concerns and disapprove of the government's surveillance activities. But, 37 percent of respondents said they do approve and only 35 percent said they are "very concerned" about their privacy.

A Pew poll released around the same time told a slightly different story, showing America split down the middle -- 48 percent approving of NSA surveillance and 47 percent disapproving.

Whatever opposition there may be to programs like PRISM, it may not translate into public support for Snowden. The Pew data showed 54 percent of Americans in support of prosecuting him, while 38 percent oppose it.

However, while watchdog groups may laud Snowden as a hero, and while the government tries to paint him as a villain, it's important to keep an open mind and healthy sense of skepticism.

"There's still a lot we don't know about his case, and a lot of information is out there that may or may not be correct," Newman cautioned.

The case does highlight very real dangers, though, Edwards emphasized.

"We realize now that our government has interpreted laws in ways that violate the constitutional rights of citizens," she said. "Snowden revealed that the U.S. has become a surveillance state because of secret courts and legal decisions."