RIVERSIDE, Calif. (CN) - Family members of six victims killed in the San Bernardino terror attack filed court papers Thursday supporting the FBI's efforts to unlock the iPhone of the Syed Farook, while Silicon Valley heavyweights got behind Apple.
The relatives of Sierra Clayborn, Aurora Godoy, Damian Meins, Larry Daniel Eugene Kaufman, Yvette Velasco and Beth Houser filed the brief. The six victims lost their lives, along with eight others, after Farook and his wife Tashfeen Malik opened fire during a holiday party at the Inland Regional Center in San Bernardino on Dec. 2.
Google, Yahoo, Twitter and Facebook also filed amicus briefs in support of Apple on Thursday.
The government meanwhile rounded up support from law enforcement groups including the California State Sheriffs Association, California Police Chiefs' Association, California Peace Officers' Association and other groups.
U.S. Magistrate Judge Sheri Pym ordered Apple to help the FBI unlock Farook's iPhone 5c - a company phone owned by San Bernardino County, where the shooter was employed as health inspector.
The government followed that with a motion to compel Apple to assist FBI technicians who have been unable to unlock the phone and get around its auto-erase feature.
Apple formally defied the order in papers filed last week. A hearing on the motions is scheduled for March 22 in Pym's courtroom in Riverside.
Attached to the San Bernardino relatives' 22-page brief is a copy of a letter from Kaufman's father Mark Sandefur to Apple CEO Tim Cook, in which he implored the company to help unlock the phone.
"Recovery of information from the iPhone in question may not lead to anything new," Sandefur wrote. "But what if there is evidence pointing to a third shooter? What if it leads to an unknown terrorist cell? What if others are attacked, and you and I did nothing to prevent it?"
Attorney Stephen Larson, a former federal prosecutor and federal judge, filed the brief on behalf of the families. Larson is now a partner with the law firm Larson O'Brien.
In the brief, the attorney challenges Apple's argument that privacy of millions of Americans will be compromised, and asserts the tech giant only trying to "obtain sympathy for its cause."
"What is implicated here is the United States' ability to obtain and execute a valid warrant to search one phone used by a terrorist who committed mass atrocities," the brief states.
Not all the victims' relatives are standing behind the government.
Anies Kondoker was also killed in the attack. Her widower said the focus should be on stronger gun laws and that he is skeptical that terrorists would have left anything of investigative value on the phone because it was a work phone.
"When I first learned Apple was opposing the order I was frustrated that it would be yet another roadblock," Salihin Kondoker wrote in a letter to Pym. "But as I read more about their case, I have come to understand their fight is for something much bigger than one phone. They are worried that this software the government wants them to use will be used against millions of other innocent people. I share their fear."
On Wednesday, the ACLU also filed a brief in support of the tech company. Digital rights group Electronic Frontier Foundation joined the chorus of privacy and civil rights groups that have jumped in to challenge the court order that requires Apple to assist the FBI.
"The court order is akin to the government dictating a letter endorsing backdoors and forcing Apple to sign its forgery-proof name at the bottom,'' the EFF's David Greene said in a statement.
Human Rights Watch, Airbnb, eBay, Kickstarter, LinkedIn, Meetup, Reddit, Squarespace, AT&T, Intel, Amazon.com, Dropbox, Evernote, Microsoft, Mozilla, Pinterest, Snapchat, WhatsApp and Yahoo are also supporting Apple.
The brief filed by Facebook accused the government of overreach in its use of the centuries-old All Writs Act to demand that Apple help unlock the phone, and said that the FBI could not lawfully ask the tech company to break security on its own products.
"Amici, in short, have no interest in shielding those who break the law. But amici reject the government's unsupported assertion that the law allows it to commandeer a company's own engineers to undermine their products' data security features," Facebook's brief states.
But a brief filed by Federal Law Enforcement Officers Association, the Association of Prosecuting Attorneys and the National Sheriffs' Association on Wednesday urged Pym to force Apple to comply with the order and called the company's position a "dangerous one."
"First, Apple's refusal to provide assistance has far-reaching public safety ramifications by making it difficult, and in some cases impossible, for law enforcement to fulfill its obligation to investigate crimes, protect the public by bringing criminals to justice, and enforce the law," the 15-page filing states. "Second, if Apple were to prevail, the public at large may itself think twice about cooperating with law enforcement when called upon to do so."
Thirty-two law professors also filed amicus briefs supporting Apple. United Nations Special Rapporteur David Kaye also wrote a letter to Pym earlier this week urging her to vacate her Feb. 16 order.
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