Amazon Web Services dropped WikiLeaks material from its servers on Tuesday, a move that is widely assumed to be a direct response to pressure from the Senate Homeland Security Committee. A statement from Amazon disputed that, stating that they kicked WikiLeaks off for violating the terms of service: “For example, our terms of service state that ‘you represent and warrant that you own or otherwise control all of the rights to the content… that use of the content you supply does not violate this policy and will not cause injury to any person or entity.’”

It’s not the first time the company has pulled something like this. Just last year, Amazon “remotely deleted” the e-editions of two books that customers had already downloaded to their Kindle readers, after it was discovered that the books’ seller did not have the rights to them. (And just their luck: the public relations headache that resulted from the deletion was no doubt amplified by the fact that the two books in question happened to be by George Orwell.) As Gawker’s Ryan Tate notes, Amazon’s policy of which content partners it will protect, and when, and why, is inconsistent and unpredictable, to say the least.

TechPresident’s Micah Sifry reported Wednesday that, according to the Senate Homeland Security Committee spokesperson Leslie Phillips, the committee has not contacted any other tech companies whose services WikiLeaks has utilized, like Twitter or Facebook. However, Phillips added, “Senator Lieberman hopes that what has transpired with Amazon will send a message to other companies.”

At least one other company got that “message” loud and clear. Open-source data visualization program Tableau Public also removed WikiLeaks-published visualizations from its site, a decision which a statement on the Tableau website acknowledges was made in response to the public request by Lieberman to do so.

So what does that mean for the rest of us? CJR assistant editor Lauren Kirchner spoke with Ethan Zuckerman, researcher for the Berkman Center for Internet and Society—who has written about the tricky intersection of public space (the Internet) and private infrastructure (service providers)—about the broader implications of this news.

Why do you think WikiLeaks chose Amazon servers in the first place?

My guess is that it’s a very easy way to buy a lot of server capacity really fast. I mean, WikiLeaks was facing two things at the same time: they were under tremendous load, probably in the neighborhood of ten to fifteen gigabits per second of traffic, and at the same time they were experiencing a DDos [distributed denial-of-service] attack of two to four gigabits per second the first time around, and about ten the second time around. It’s a pretty common tactic when you’re under DDoS to try to get onto a pretty big server farm. If you’re both trying to serve an enormous amount of traffic and cope with DDos, Amazon makes very good sense, actually. You’re going to pay for it, but I don’t think that was their big constraint; their big constraint was trying to stay up in the face of all the interest in the documents.

To what extent is a company like Amazon legally responsible for documents it hosts?

That is an incredibly complicated question. Everything has to go under the I Am Not a Lawyer disclaimer here. Essentially, there are real questions about what the legal liability is, in dealing with any of the WikiLeaks material. Different lawyers might answer that question very differently. Generally speaking, though, there are a good number of protections of internet service providers against things like copyright infringement, through things like the DMCA [Digital Millennium Copyright Act of 1998], which basically says, as long as you follow this process correctly, you’re not going to be held liable for contributory copyright infringement. But to the best of my knowledge, no one’s put anything together essentially saying, here’s the policy you should go through if you are alerted that you are holding government secrets. I think where I and Rebecca [MacKinnon] and others have criticized Amazon’s move is that it’s not clear that they actually received any legal notice; it sounds like what it amounted to was essentially just political pressure.

I know this is just conjecture here, but if Amazon had pushed back against the Senate Homeland Security Committee, do you think the Committee would have threatened legal action? What’s the nature of the threat there?

Lauren Kirchner is a freelance writer covering digital security for CJR. Find her on Twitter at @lkirchner