Apple vs. the F.B.I.: the battle over a terrorist's locked iPhone could have a huge impact on the future of digital privacy.

• Author: Smith, Patricia
• Position: NATIONAL - Essay

After killing 14 people at an office party in San Bernardino, California, in December, Syed Rizwan Farook and his wife died in a shoot-out with police. Farook, who claimed to be acting on behalf of the terrorist group ISIS, left behind a locked iPhone 5c.

The F.B.I. wants to know what's on that phone. Finding out who Farook was in touch with and where he traveled in the time leading up to the massacre might help prevent future attacks, officials say. So they went to federal court and got a warrant requiring Apple to bypass the security system built into the phone.

But Apple, one of the world's most powerful technology companies, is fighting the court order, saying the government is overstepping its bounds. Complying with the order, Apple says, would set a dangerous precedent and threaten the privacy rights of Americans.

"While we believe the F.B.I.'s intentions are good, it would be wrong for the government to force us to build a back door into our products," says Apple CEO Timothy Cook. "And ultimately, we fear that this demand would undermine the very freedoms and liberty our government is meant to protect. "

The fight between Apple and the F.B.I. could turn out to be a watershed moment that helps define constitutional rights like privacy in today's wired world. The issue is important because people's lives have become so intertwined with their smartphones and other gadgets. And tech companies like Apple and Google control massive amounts of user data.

The Fourth Amendment to the Constitution prohibits "unreasonable searches and seizures" (see box), and courts have often interpreted that language as guaranteeing Americans certain privacy rights. When the Founding Fathers wrote the Bill of Rights in the late 1700s, however, they had someone's home or property in mind. They couldn't have imagined applying those protections to 21st-century technology.

"The stakes are high," says Marc Rotenberg of the Electronic Privacy Information Center. "This case is about how constitutional principles such as the Fourth Amendment and the First Amendment apply in the digital age."

An Unbreakable Lock?

In some ways, the fight between Apple and the F.B.I. boils down to this question: Should you be able to lock your phone so securely that even the F.B.I. can't open it? The F.B.I., the Obama administration, and police officials say no. After all, they reason, homes and cars don't have unbreakable locks. With a legal warrant from a judge, an officer should be able-as they have in the past--to search any of those. Therefore, they say, criminals shouldn't be able to buy a handheld computer--what an iPhone essentially is--that keeps its secrets forever.

In its battle with Apple, the F.B.I. maintains it's asking for help to break into only a single phone, not phones everywhere. That requires overriding Apple's security setting that erases data after 10 incorrect attempts at entering a phone's passcode.

"We simply want the chance, with a search warrant, to try to guess the terrorist's passcode without the phone essentially self-destructing and without it taking a decade to guess correctly," says F.B.I. Director James Comey. "We don't want to break anyone's encryption or set a master key loose on the land."

Many Americans seem sympathetic to the F.B.I.'s argument: 51 percent back the government in this dispute, with 38 percent saying they side with Apple, according to a recent Pew Research Center survey.

But Apple says the government is missing the point: People's phones are a record of their most intimate thoughts and personal information, including financial records, friends' addresses, location data, personal photos, and more. Apple built its recent iPhones to keep that data private, and it says nothing less than the future of privacy is at stake in this fight.

The F.B.I. wants Apple to write software that would let it keep guessing until it hits the code. Apple says that would, in effect, give the government--and perhaps hackers--the ability to get into anyone's phone. And Apple isn't just concerned about the U.S. government: Once created, a decryption tool could be used by authoritarian regimes around the world against human rights activists or anyone else who dares to stand up to them.

"The government suggests this tool...