Facebook has been at the center of a controversy involving its moderation policies and The Pirate Bay, a popular Bittorrent tracker that was found guilty of copyright infringement by a Swedish court last month. Since early April, Facebook has enforced a “site-wide” ban on links to The Pirate Bay – including those in private messages.

This practice may run afoul of federal wiretapping statutes that bar service providers from “intercepting” private messages, according to an article that appeared on Wired Threat Level last week. Wired quotes Kevin Bankston, a senior attorney for the Electronic Frontier Foundation, who explains that Facebook’s filtering raises “serious questions about whether Facebook is in compliance with federal wiretapping law.”

It’s important to draw a distinction between the traditional notion of “wiretapping” and Facebook’s “interception” of user messages, which doesn’t involve any human intervention. Regardless of how the courts may interpret ancient laws like the 1986 Electronic Communications Privacy Act, an automated computer system flagging and deleting certain strings from user messages simply isn’t comparable to a third party secretly listening in on a private phone conversation.

Besides, Facebook makes clear to its users from the get-go that their messages and postings are subject to a set of rules (which Facebook lays out in plain English). If Facebook believes a message or posting is against the rules, it can block or remove it. This is not an unreasonable rule; many online discussion forums have enforced similar policies since the Web’s early days. Such filtering is possible only if sites can “examine” messages to identify misconduct.

Critics of Facebook’s filtering policies have rightly pointed out that even legal Pirate Bay links are being blocked. While this is a valid argument, it belongs on the feedback section of Facebook’s Site Governance page – not in a court of law. It isn’t the role of government to second-guess content judgments reached in good faith by social networking sites. Facebook must weigh a range of competing concerns in deciding how to cater to its hundreds of millions of diverse users. The same message that one user might consider “spammy” or malicious might be seen in a totally different light by another user. Add into the equation concerns over reputation and even potential copyright infringement liability, and it’s easy to see why Facebook has to make tough – and controversial – decisions all the time.

While I agree with Bankston that the legal ramifications of Facebook’s practices are far from clear, I’m concerned about the prospect of wiretapping laws being used against websites that moderate communications between users. If filtering Pirate Bay links from user messages constitutes illegal wiretapping, then it would seem that any social network or discussion forum that monitors and removes content from user-to-user communications would be in violation of federal law.

What would it mean for the Internet if websites were barred from moderating messages sent between users? AOL might not be able to “kids only” chat rooms; instant messaging services might be even more spam-ridden than they already are; and yoursphere, a social-networking site “just for kids,” likely wouldn’t even be able to exist.

Decisions about how to operate private online ecosystems are best left to individual firms competing in an open marketplace. Prohibiting website operators from moderating user messages may not bother people who don’t mind spam or porn (or Pirate Bay links), but what about people who desire a social network in which certain kinds of speech are off-limits?

One of the best aspects of the Web is that choices are abundant. If you don’t like one social networking site’s policies, you can go someplace else. Users can already send around links to Pirate Bay torrents through countless other social networking sites, email providers, and instant messaging services. Gmail, AIM, Ning, and Skype are just some examples of free online services that do not censor Pirate Bay links. Heck, if none of these options are satisfactory, you can even build your very own social network with free software like BoonEx and spread around all the Pirate Bay links you want.

Unlike with wiretaps, law enforcement agents are not required by federal statutes to obtain search warrants before employing pen registers or trap and trace devices. These devices record non-content information regarding telephone calls and Internet communications. (Of course, “non-content information” has quite a bit of content – who is talking to whom, how often, and for how long.)

The Electronic Privacy Information Center points out in a letter to Senate Judiciary Committee Chairman Patrick Leahy (D-VT) that the Department of Justice has consistently failed to report on the use of pen registers and trap and trace devices as required by law:

The Electronic Communications Privacy Act requires the Attorney General to “annually report to Congress on the number of pen register orders and orders for trap and trace devices applied for by law enforcement agencies of the Department of Justice.” However, between 1999 and 2003, the Department of Justice failed to comply with this requirement. Instead, 1999-2003 data was provided to Congress in a single “document dump,” which submitted five years of reports in November 2004. In addition, when the 1999-2003 reports were finally provided to Congress, the documents failed to include all of the information that the Pen Register Act requires to be shared with lawmakers. The documents do not detail the offenses for which the pen register and trap and trace orders were obtained, as required by 18 U.S.C. § 3126(2). Furthermore, the documents do not identify the district or branch office of the agencies that submitted the pen register requests, information required by 18 U.S.C. § 3126(8).

EPIC has found no evidence that the Department of Justice provided annual pen register reports to Congress for 2004, 2005, 2006, 2007, or 2008. “This failure would demonstrate ongoing, repeated breaches of the DOJ’s statutory obligations to inform the public and the Congress about the use of electronic surveillance authority,” they say.

It’s a good bet, when government powers are used without oversight, that they will be abused. Kudos to EPIC for pressing this issue. Senator Leahy’s Judiciary Committee should ensure that DoJ completes reporting on past years and that it reports regularly, in full, from here forward.