A telephone with a picture of the Capitol Dome on it is shown. (Franckreporter/GETTY IMAGES)

The White House on Monday said consumers should be allowed to “unlock” their phones and tablets and switch wireless networks after their contracts run out without fear of breaking the law.

Most mobile gadgets contain software that prevents a smartphone user on, say, AT&T’s network from switching the device to run on a rival system. The blocks can be easily removed with programs that can be downloaded from the Web.

In January, the Library of Congress made unlocking a violation of a little-known provision of copyright law. Anyone who tried to do so could face criminal and civil penalties.

The decision quickly sparked an outcry from online activists. Taking to social media, blogs and the White House’s own protest forum, they collected over 114,000 signatures in just a few weeks.

In response, the Obama administration said it would support legislation to overturn the decision by the Library of Congress, which houses the U.S. Copyright Office. The White House also called on the Federal Communications Commission to intervene.

“It’s common sense, crucial for protecting consumer choice, and important for ensuring we continue to have the vibrant, competitive wireless market that delivers innovative products and solid service to meet consumers’ needs,” David Edelman, President Obama’s senior Internet adviser, wrote in a blog.

For now, cellphone unlocking remains illegal. But the quick response by the White House demonstrates how officials have become responsive to Washington’s emerging powerbase: Internet activists.

On several issues, such as an effort to crack down on Internet piracy last year, Web advocates have used grass-roots efforts and petitions to create locust like momentum for their agenda, government veterans say.

The unlocking issue “comes at a moment when everyone in the country is looking at Washington and saying they don’t seem to get anything done. And then you get a couple smart people who are passionately against a rule that the government adopts and through blogs and a petition get the White House to respond in 60 days,” said Blair Levin, a former FCC chief of staff during the Clinton administration.

Initially, very few policymakers took notice of the Library of Congress’s decision. In October, after a one-year review of the issue, the agency said it would make unlocking illegal beginning Jan. 26.

The problem, the agency argued, was that phones and tablets have copyrighted software, which must be circumvented to get to the codes that can unlock the devices. The only way to do it legally is to get permission from wireless carriers.

The quiet change in rules was soon discovered by some tech policy experts, including a 25-year-old former House Republican researcher, Derek Khanna, who wrote a critical article about the decision that was published by several online news outlets.

The piece went viral, and other activists took the matter to the White House protest forum, which requires a response from officials once a petition gets 100,000 signatures.

“This was a bipartisan effort, one that had Google’s Vint Cerf [company vice president and its ‘chief Internet evangelist’] in agreement with Tea Party Nation,” Khanna said. “This is about creating smart tech policy, and there are a lot of people out there who feel the same way.”

On Monday, the Library of Congress said it would review its policies. In a statement, it said that “the question of locked cellphones has implications for telecommunications policy and . . . would benefit from review and resolution in that context.”

The FCC also said Monday it supports cellphone unlocking.

Chairman Julius Genachowski said the FCC is exploring if “the agency, wireless providers, or others should take action to preserve consumers’ ability to unlock their mobile phones.”

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