The Librarian of Congress wields a surprising amount of power over the mobile devices we use every day. Once every three years, the head of the US Library of Congress is responsible for handing out exemptions to the anti-circumvention provisions in the Digital Millennium Copyright Act (DMCA).

Further Reading Unlocking new cell phones to become illegal on Saturday

The Librarian of Congress has thus been able to decide whether it's legal to jailbreak or unlock phones and other devices. Jailbreaking (or "rooting") provides greater access to the underlying hardware functionality of devices like iPhones and Android phones, letting users install software they otherwise wouldn't be able to use. Unlocking allows a cellular device to be used with any compatible carrier network, for example to use an AT&T phone on T-Mobile.

James Billington, 86, has been the Librarian of Congress since he was appointed by President Ronald Reagan in 1987. Billington is retiring today, and the Obama administration has to find a replacement. Deputy Librarian David Mao will fill the role temporarily until a new librarian is nominated by Obama and confirmed by the Senate.

In the past few years, Billington has drawn the ire of consumer advocates and technology users by making it illegal to unlock cell phones and illegal to jailbreak tablet computers. (Separately, carriers have agreed to unlock phones for consumers who pay off their contracts or installment plans, but the lack of a DMCA exemption meant that consumers weren't allowed to unlock phones on their own.)

"The new batch of exemptions illustrate the fundamentally arbitrary nature of the DMCA's exemption process," Ars wrote after the last exemptions were handed out in October 2012. "For the next three years, you'll be allowed to jailbreak smartphones but not tablet computers. You'll be able to unlock phones purchased before January 2013 but not phones purchased after that. It will be legal to rip DVDs to use an excerpt in a documentary, but not to play it on your iPad. None of these distinctions makes very much sense. But Congress probably deserves more blame for this than the Librarian of Congress."

Congress gave the exemption-granting authority to the Librarian of Congress when it passed the DMCA in 1998.

The Librarian's unlocking decision was undone in August 2014 when President Obama signed a bill making it legal for consumers to unlock their phones. Yet that bill could be undone when the Librarian of Congress issues the next round of exemptions sometime this year. The proceeding has covered not just phones and tablets but video game consoles, vehicle software, 3D printers, networked medical devices, and more.

Billington announced his retirement in June, saying he would leave his post January 1, 2016. But the timetable was moved up, and now he is retiring effective today. Someone else will be responsible for handing out DMCA exemptions.

In addition to the DMCA decisions, Billington "presided over a series of management and technology failures at the library that were documented in more than a dozen reports by government watchdog agencies," The New York Times wrote when he announced his retirement. One 2013 audit by the library's inspector general "warned that millions of items, some from as far back as the 1980s, remained piled in overflowing buildings and warehouses, virtually lost to the world," and that only a small fraction of the library's 24 million books are available to read on the Internet.

"[T]ech advocates are pushing for an Internet-savvy replacement" for Billington, while a pro-copyright alliance of major copyright-holding corporations is also weighing in, a Politico article said yesterday. A source told Politico that the Obama administration approached Steve Jobs biographer and Aspen Institute CEO Walter Isaacson about the job but that he took his name out of consideration.

The Electronic Frontier Foundation urged Obama to appoint a Librarian of Congress who would "serve as a zealous advocate for user's rights." In the current DMCA exemption proceeding, the EFF said it is "fighting to get new rules for repairing and modifying cars, bringing abandoned video games back online, ripping video streams, and more. The Copyright Office runs the rulemaking, and the Librarian generally, but not always, defers to its judgment. A Librarian that was engaged on users' rights could be a much more active voice in that process."

The next librarian may not be allowed to serve nearly as long as Billington, as some lawmakers are pushing for a 10-year limit to replace the current lifetime appointment.