The FBI and Apple are facing off over an iPhone again. What's going on?

Julia Carrie Wong in San Francisco
Photograph: Mark Ralston/AFP/Getty Images

Three years after the high-stakes battle between Apple and the US federal government over unlocking a suspected terrorist’s iPhone, a new standoff is shaping up between the privacy-minded tech company and the Trump administration.

On Monday, the US attorney general, William Barr, called on Apple to help the Federal Bureau of Investigation (FBI) unlock two iPhones related to the fatal shooting of three Americans at a Florida naval base in December. The shooting, by a Saudi air force cadet who was training with US forces, is now considered an act of terrorism, Barr said.

Related: Inside the FBI's encryption battle with Apple

The attorney general complained that Apple had “not given us any substantive assistance”. “This situation perfectly illustrates why it is critical that investigators be able to get access to digital evidence once they have obtained a court order,” he said.

The demand for assistance in unlocking a suspected terrorist’s iPhone echoes the 2016 dispute between Apple and the FBI, which sought access to information stored on the iPhone of one of the killers in the San Bernardino, California, mass shooting.

Apple responded to Barr in a statement Monday evening, saying that it rejected the idea that it had not helped law enforcement, and noting that it had responded to the FBI’s requests for assistance within hours, and had already provided investigators with “many gigabytes of information”.

But Apple also reiterated its opposition to weakening encryption, noting that “there is no such thing as a backdoor just for the good guys”. “Backdoors can also be exploited by those who threaten our national security and the data security of our customers,” the company said in a statement.

The information that Apple provided the government was likely data stored on Apple’s cloud. The information that the FBI still wants is the data stored directly on the phone, which is only accessible to a user with the phone’s password – and not to Apple.

Apple is one of many tech companies that have limited the amount of user data they store on their own servers in the wake of the Edward Snowden revelations, in part in order to avoid being subject to government requests.

On Tuesday, Donald Trump waded into the dispute with a tweet lashing out at Apple for refusing to “unlock phones used by killers, drug dealers and other violent criminal elements”.

The standoff over the San Bernardino killer’s phone ignited when Apple refused to comply with a federal court order to help the FBI unlock the phone. At the time, the chief executive Tim Cook pushed back forcefully on the government’s request, which he said would “undermine the very freedoms and liberty our government is meant to protect”. Civil liberties groups rallied behind Apple in the court battle, but the case became moot when the FBI broke into the phone with the help of a private company.

The dispute lay dormant for several years, until October 2019, when Barr revived it with a letter to Facebook calling for a backdoor in the end-to-end encryption that the company plans to implement in all its messaging apps.

The UK home secretary and Australian minister for home affairs joined Barr in his letter to Facebook, prompting global criticism from security experts and privacy experts.

“This is bigger than any single iPhone,” the American Civil Liberties Union tweeted on Monday. “The government’s demand would weaken the security of millions of iPhones, and is unconstitutional.”