The President Barack Obama administration said Monday that it made "common sense" for Americans to legally have the power to unlock their mobile phones, so they could use them on a compatible carrier of choice without fear of being sued or facing criminal penalties.

"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," White House aide R. David Eldelman wrote Monday in response to a whitehouse.gov petition demanding the administration enter the mobile-phone-unlocking fray.

A whitehouse.gov petition reached 100,000 signatures last month, forcing the administration to respond publicly about a recent decision by copyright regulators making it illegal to unlock mobile phones purchased after January 26. Unlocking enables a phone to operate on a compatible carrier of a consumer’s choosing.

"This is terrific news," Derek Khanna, one of the petition's main backers, said in a telephone interview.

The administration said it would support legislation to change course – and also allow tablets to be unlocked legally – and urged the Federal Communications Commission to intervene, too. Julius Genachowski, the FCC chairman, said the commission was, indeed, looking into the matter.

"From a communications policy perspective, this raises serious competition and innovation concerns, and for wireless consumers, it doesn't pass the common sense test," he said in a statement.

The U.S. Copyright Office ended the practice of granting an unlocking exemption to the Digital Millennium Copyright Act last year. The DMCA makes it illegal to "circumvent a technological measure that effectively controls access" to copyrighted material, in this case software embedded in phones that controls carrier access.

The carriers, however, last year told the Copyright Office, which every three years re-examines exemptions to the DMCA, that they did not oppose individuals unlocking their phones. Many carriers provide the service today to individuals, despite the decision.

Among the reasons the Copyright Office changed course in October was because many carriers and phone makers sold unlocked phones and would also unlock them for their customers. Unlocking was denied for the first time for tablets, too, because an "ebook reading device might be considered a tablet, as might a handheld video game device."

Before unlocking mobile phones was first exempted in 2006 and again in 2010, the carriers never sued individuals for unlocking their own phones. When unlocking was exempted and allowed, the carriers and phone makers were busy successfully suing illicit businesses that bought throw-away phones by the thousands, unlocked them, and shipped them overseas.

But under the changeover, there's nothing preventing the carriers from suing individuals and abandoning the practice of unlocking mobile phones for their customers.

Here is the White House's full response Monday: