Late Wednesday, Mr. Greenwald, a lawyer and longtime blogger, published an article in the British newspaper The Guardian about the existence of a top-secret court order allowing the National Security Agency to monitor millions of telephone logs. The article, which included a link to the order, is expected to attract an investigation from the Justice Department, which has aggressively pursued leakers.

“The N.S.A. is kind of the crown jewel in government secrecy. I expect them to react even more extremely,” Mr. Greenwald said in a telephone interview. He said that he had been advised by lawyer friends that “he should be worried,” but he had decided that “what I am doing is exactly what the Constitution is about and I am not worried about it.”

Being at the center of a debate is a comfortable place for Mr. Greenwald, 46, who came to mainstream journalism through his own blog, which he started in 2005. Before that he was a lawyer, including working 18 months at the high-powered New York firm Wachtell, Lipton, Rosen Katz, where he represented large corporate clients.

“I approach my journalism as a litigator,” he said. “People say things, you assume they are lying, and dig for documents to prove it.”

Mr. Greenwald’s writings at The Guardian — and before that, for Salon and on his own blog — can resemble a legal brief, with a list of points, extended arguments and detailed references and links. As Andrew Sullivan, a frequent sparring partner and sometime ally, put it, “once you get into a debate with him, it can be hard to get the last word.”

While Mr. Greenwald notes that he often conducts interviews and breaks news in his columns, he describes himself as an activist and an advocate. But with this leak about the extremely confidential legal apparatus supporting the Foreign Intelligence Surveillance Act, he has lifted the veil on some of the government’s most closely held secrets.

The leak, he said, came from “a reader of mine” who was comfortable working with him. The source, Mr. Greenwald said, “knew the views that I had and had an expectation of how I would display them.”

Mr. Greenwald’s experience as a journalist is unusual, not because of his clear opinions but because he has rarely had to report to an editor. He began his blog Unclaimed Territory in 2005 after the news of warrantless surveillance under the Bush administration. When his blog was picked up by Salon, said Kerry Lauerman, the magazine’s departing editor in chief, Salon agreed that Mr. Greenwald would have direct access to their computer system so that he could publish his blog posts himself without an editor seeing them first if he so chose.

“It basically is unheard of, but I never lost a moment of sleep over it,” Mr. Lauerman said. “He is incredibly scrupulous in the way a lawyer would be — really, really careful.”

The same independence has carried over at The Guardian, though Mr. Greenwald said that for an article like the one about the N.S.A. letter he agreed that the paper should be able to edit it. Because he has often argued in defense of Bradley Manning, the army private who was charged as the WikiLeaks source, he said he considered publishing the story on his own, and not for The Guardian, to assert that the protections owed a journalist should not require the imprimatur of an established publisher.

Mr. Greenwald said he has had to get up to speed in the security precautions that are expected from a reporter covering national security matters, including installing encrypted instant chat and e-mail programs.

“I am borderline illiterate on these matters, but I had somebody who is really well-regarded actually come and physically do my whole computer,” he said.

That computer is in Brazil, where Mr. Greenwald spends most of his time and lives with his partner, who cannot emigrate to the United States because the federal government does not recognize same-sex marriages as a basis for residency applications.

Mr. Greenwald grew up in Lauderdale Lakes, Fla., feeling like an odd figure. “I do think political posture is driven by your personality, your relationship with authority, how comfortable are you in your life,” he said. “When you grow up gay, you are not part of the system, it forces you to evaluate: ‘Is it me, or is the system bad?’ ”

By the time Mr. Greenwald was studying law at New York University, “he was always passionate about constitutional issues and issues of equal justice and equal treatment,” said Jennifer Bailey, now an immigration lawyer with a nonprofit organization in Maine, who shared a tiny apartment with Mr. Greenwald in the early 1990s.

She emphasized that his passion did not translate into partisanship. “He is not a categorizeable guy,” Ms. Bailey said. “He was not someone who played party politics. He was very deep into the issues and how it must come out. He was tireless and relentless about pursuing this. Nobody worked longer hours.”

As Mr. Greenwald tells it, the last decade has been a slow political awakening. “When 9/11 happened, I thought Bush was doing a good job,” he said. “I was sucking up uncritically what was in the air.”

His writing has made him a frequent target from ideological foes who accuse him of excusing terrorism or making false comparisons between, for example, Western governments’ drone strikes, and terrorist attacks like the one in Boston.

Gabriel Schoenfeld, a national security expert and senior fellow at the Hudson Institute who is often on the opposite ends of issues from Mr. Greenwald, called him, “a highly professional apologist for any kind of anti-Americanism no matter how extreme.”

Mr. Sullivan wrote in an e-mail: “I think he has little grip on what it actually means to govern a country or run a war. He’s a purist in a way that, in my view, constrains the sophistication of his work.”

Ms. Bailey has a slightly different take. Because of his passions, she said, “he is just as willing to make enemies of anybody.”

Article source: http://www.nytimes.com/2013/06/07/business/media/anti-surveillance-activist-is-at-center-of-new-leak.html?partner=rss&emc=rss