A broad array of technology firms joined Apple's legal fight on encryption Thursday, warning of a dangerous precedent if the company is forced to help the government break into a locked iPhone.
Three tech associations which represent Apple's main business rivals—including Google, Facebook, Microsoft and Yahoo—announced a joint brief supporting Apple's efforts to challenge an order that would require it to help unlock an iPhone used by one of the San Bernardino attackers.
"If the government arguments prevail, the Internet ecosystem will be weakened, leaving Internet users more vulnerable to hackers and other bad actors," said a statement from the Computer and Communications Industry Association, which announced a joint amicus brief with the Internet Association and the i2 Coalition of Internet infrastructure firms.
The three associations said their brief was set to be filed before the midnight deadline in federal court in California where the case is being heard.
A number of other companies and associations were expected to file briefs in the case, which has divided the American public and set off a highly charged debate about the limits of law enforcement in accessing digital devices.
"There is broad and deep concern throughout many types of companies throughout the tech industry that there is a potentially dangerous precedent in this case," said Ed Black, president and chief executive of CCIA.
"While the tech industry understands the government's desire for information, and respects its mission to keep us safe, we hope the court appropriately weighs the wider issues of security and trust that are also at stake in this case."
The case stems from the FBI's efforts to access the locked iPhone used by one of the perpetrators of the December attack in San Bernardino, California, that killed 14 people.
Apple has argued that the only way to unlock the phone is to introduce a weakened operating system, which could potentially leak out and be exploited by hackers and foreign governments.
The FBI has argued that by introducing encryption which can lock data only accessible to the user, Apple and others are essentially creating "warrant proof zones" for criminals and others that will cripple law enforcement and jeopardize public safety.
The CCIA includes Apple rivals such as Amazon, Pandora and Samsung, and the Internet Association counts as members Dropbox, Microsoft, Yahoo and Facebook. Some firms are members of both. The i2 Coalition includes Google, which is a member of all three organizations.
Some individual companies and other industry groups were also planning to file amicus briefs, which back the legal arguments of one side or the other.
Earlier this week, the digital rights groups Access Now and the Wickr Foundation filed a separate amicus brief arguing that forcing Apple to comply would undermine encryption and violate the human rights of users, both in the United States and around the world.
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