The FBI just fired back at Apple over its refusal to help it hack an iPhone

FBI Director James Comey has hit back at Apple for refusing to help unlock the iPhone of a suspected terrorist.

A US judge has ordered Apple to assist the FBI in its attempt to access encrypted data on the iPhone on San Bernardino shooter Syed Farook. But Apple argues doing so would create a dangerous precedent, and make all users less safe. CEO Tim Cook argues the move "would undermine the very freedoms and liberty our government is meant to protect."

The director of the US Federal Bureau of Investigation published a blog post on specialist legal site Lawfare on Sunday titled "We Could Not Look the Survivors in the Eye if We Did Not Follow this Lead."

In the blog, which does not directly mention Apple or the iPhone by name, Comey claims the agency doesn't want to break anyone's encryption or set loose a master key to devices like the iPhone.

He added that the case involving the San Bernardino shooter's iPhone was "quite narrow" and not intended to set a precedent.

"The San Bernardino litigation isn't about trying to set a precedent or send any kind of message. It is about the victims and justice," he wrote in his post.

It's an argument that many are likely to be dubious of, given Comey's past vocal angling for backdoors in encryption.

Kevin Bankston, director of non-profit New America's Open Technology Institute, previously told Business Insider that he believes this is about a precedent. "What the court is essentially ordering Apple to do is custom-build malware to undermine its own product's security features, and then cryptographically sign that software so the iPhone will trust it as coming from Apple," he said.

"If a court can legally compel Apple to do that, then it likely could also legally compel any other software provider to do the same, including compelling the secret installation of malware via automatic updates to your phone or laptop's operating system or other software.

"In other words, this isn't just about one iPhone, it's about all of our software and all of our digital devices, and if this precedent gets set it will spell digital disaster for the trustworthiness of everyone's computers and mobile phones."

Last week Tim Cook wrote an open letter saying he would fight the FBI over a demand to build a backdoor in the iPhone.

The FBI wants Apple to remove the limit on the number of times the passcode can be tried. It also wants Apple to modify its iOS operating system so passcodes can be input electronically. Apple argues this amounts to a backdoor it would have to write, which would later be open to abuse.

"The government suggests this tool could only be used once, on one phone," the letter on Apple.com reads. "But that's simply not true. Once created, the technique could be used over and over again, on any number of devices. In the physical world, it would be the equivalent of a master key, capable of opening hundreds of millions of locks - from restaurants and banks to stores and homes. No reasonable person would find that acceptable."