Matthew D. Green made a name for himself as the rare cryptography professor who will explain and critique the U.S. government's most controversial surveillance capabilities in layman's terms and unencumbered by a government security clearance or research contract that keeps others from speaking freely.
Green's blog is a popular destination for journalists and other academics, while thousands follow his Twitter feed. Colleagues applaud his clear analysis.
In recent weeks, Green thought his contributions to the growing public discourse surrounding the National Security Agency, including the recent revelations that it spent billions of dollars to circumvent standard encryption tools meant to protect private information across the Internet, were something his superiors at the Johns Hopkins University would encourage.
"I assumed that everybody was very supportive of this and this was a goal of the university, to be in the public eye," he said.
Then, on Monday, he got an email from Andrew Douglas, interim dean of the Whiting School of Engineering, asking him to remove a blog post he had written and posted on the university's servers offering analysis of the NSA revelations, linking to a New York Times article outlining the findings and including an image of the NSA logo.
Green's post criticized, among other things, the NSA's alleged meddling with or shaping of encryption standards and recruiting U.S. companies to help them ensure access to encrypted information through "back doors."
The "worst possible hypothetical" for the agency's reach that he had discussed with others was "true on a scale I couldn't even imagine," he wrote.
Green said on Twitter that Douglas told him to remove the blog post or get a lawyer. When that demand created a storm of criticism, the university quickly changed course.
The email blindsided Green, he said in an interview Tuesday.
"I had no idea that this was even an issue within the Johns Hopkins network or campus," he said.
Many of his supporters in academia were surprised but also angry, as were First Amendment and academic-rights advocates.
Not only did the university's action represent a blatant attack on the freedom and responsibility of academics to tell the truth and offer their expertise on issues of public importance, they said, but it also stifled the voice of a "rising star" in cryptography, one of few people able to explain the NSA revelations.
"The original post that Matthew Green wrote was not just any blog post. It was widely circulated and talked about a lot online because it was a respected cryptographer expressing shock at what had been revealed," said Jay Rosen, a New York University journalism professor and free-speech advocate who wrote a piece criticizing Hopkins for The Guardian, the British newspaper that helped break the NSA story based on documents leaked by former NSA contractor Edward Snowden.
"The piece was a hugely important contribution to public debate on the limits of state power," Rosen said. "Any request from a university to unpublish your thoughts would be troublesome in the extreme, but the request to unpublish a post that had been so integral to public debate is even more extreme."
On Monday, as Green, Rosen and many others took to the Internet to voice their concerns with Hopkins' decision, officials immediately began backpedaling.
A review of the decision was launched, and Green was told he could repost the piece by the end of Monday. On Tuesday, officials acknowledged that they had mishandled the situation and should not have asked that the blog post — which was a mirror copy of a post on Green's own blog, which was never removed — be taken down. Douglas also wrote an apology to Green.
"I realize now that I acted too quickly, on the basis of inadequate and — as it turns out — incorrect information," Douglas wrote.
Dennis O'Shea, a university spokesman, said the blog post was noticed initially by an employee of the Johns Hopkins Applied Physics Lab, which does work for the NSA and whose employees are under some of the security restrictions that Green is free from. (He has been offered clearances in the past, but has turned them down in an effort to remain an independent voice, he said.)
That employee, who was not identified, alerted an employee at Hopkins' Homewood campus, where Green works, and that employee told Douglas, O'Shea said.
Douglas wrote that he is "wholly supportive of academic freedom" and apologized for having "undercut" Green's reputation.
"I am also aware of the contributions you are making to your field of information security and of the relevance of your comments to the important public debate that is now under way," Douglas wrote.
He also said his motivation was to protect the university and Green from "legal consequences."
Many who immediately raised concerns about the blog post's removal and were happy to see the university reverse course said the fact that the decision was made at all remains concerning.
Christopher Soghoian, a friend of Green's who was briefly enrolled in the same Hopkins doctoral program, is now the American Civil Liberties Union's principal technologist and senior policy analyst with its Project on Speech, Privacy and Technology.
Soghoian said the incident could raise questions about the Applied Physics Laboratory and the amount of influence it has over other parts of the university.
"Even if no one at the NSA picked up the phone, there may have been some self-censorship coming out of APL hoping to preserve their good working relationship with the NSA," Soghoian said.
O'Shea said that the message from the lab employee was meant "only as an FYI" and that no directive ever came from the U.S. government or the NSA to have the blog post removed.
The NSA could not be reached for comment late Tuesday.
Soghoian also said it raises the question of whether Green's contributions to the nation's understanding of a critical public policy issue are valued by Hopkins.
"He's a good computer scientist, his research is good, but what Matt brings to the table that's unique is his ability to make this stuff salient to the average person," he said. "That is an extremely rare skill. ... If they don't realize they have a star on their hands, they should."
Matt Blaze, an associate professor of computer and information science at the University of Pennsylvania whose research focuses on cryptography, said the "knee-jerk reaction" of Hopkins officials was disconcerting.
"It's nice that it was resolved," Blaze said, "but it's very disturbing that it happened in the first place."
Green is "one of the leading thinkers in this area, and this is not just about his right to speak out," Blaze said. "It's disturbing that first of all, an administrator would kind of censor first and ask questions later, and also that this was really only able to be resolved because Matthew was confident and had the wherewithal to push back."
Rosen said it was particularly troublesome that university administrators would act so quickly to remove a blog post that was written with great care, and by a university professor making a national name for himself.
"You don't tell your best people to shut up," Rosen said. "At this point, in 2013, to ask a professor to take down a blog post without knowing how embedded that blog post is in online discussion? Not smart."
Rosen said he would start an uproar at NYU if such censorship happened there, and he was surprised more Hopkins professors weren't calling for answers Tuesday. O'Shea said he hadn't heard of any formal protest as of Tuesday afternoon.
Green said he has heard privately from many colleagues supporting him, and he appreciated Douglas' apology and the university's reversal.
"I think everybody acted too quickly, and now everybody realizes that," he said.
As for the NSA, he still has grave concerns about its activities, he said.
He teaches some of the brightest minds in the region, many of whom will end up working for the NSA and its many contractors in the area, he said.
"Everything inside of me tells me that the NSA is a bunch of very good, law-abiding people who really are here to protect our Bill of Rights and keep our freedoms safe," he said. "But every now and then I have this paranoid thought that maybe I'm wrong about that."