Image: New York County District Attorney's Office

New York County District Attorney Cyrus Vance has renewed a call for federal legislation requiring Apple to make iOS warrant-friendly.

In a report released on Thursday at the launch of the Manhattan DA's new cyberlab, Vance revealed there are now over 400 locked iPhones sitting with New York County that could be used to investigate serious crimes if only Apple would or rather could help.

The DA argues that law-enforcement agencies do not want a backdoor to Apple and Google products, but rather a return to pre-September 2014, when Apple's encryption didn't prevent them from carrying out a search warrant on an iPhone.

In a speech at the launch, Vance said the report showed that requiring smartphone makers to retain the ability to extract data will not increase users' risks of being hacked.

He said the report concluded that, "Doing nothing about this problem will perpetuate an untenable arms race between private industry and law enforcement, and that federal legislation is our only chance to lay these arms aside".

Apple released iOS 8 in September 2014 with a new encryption method that prevented access to stored data unless the password was known. It triggered a drawn-out skirmish between Apple and US law enforcement that came to a head in February over the FBI's fight to have Apple unlock the San Bernardino shooter's iPhone 5c.

Apple defied a court order demanding it build a special version of iOS to get around limits on brute-forcing iOS pass codes, arguing it would raise security risks for all iPhone users. The FBI eventually unlocked the device without Apple's help, despite earlier FBI claims that accessing the data was impossible without Apple's assistance.

Vance's office says 10 percent of the locked iPhones in the DA's cyberlab are related to homicide or attempted-murder cases, and nine percent are related to sex crimes.

While Vance has presented similar numbers previously, the call for federal legislation could be given a popular boost by president elect Donald Trump, who previously called for a boycott on Apple products when it refused to help the FBI.

Vance said the Manhattan DA's office now needs its 2,200 square foot cyberlab to deal with the sheer volume of digital evidence.

"Nearly every crime against Manhattan residents and institutions involving digital evidence will engage the resources and expertise of this lab," he said.

"With a dedicated space for our prosecutors, investigators, and analysts to work together on fast-moving investigations, New York City is better equipped than ever to combat the rising tide of cybercrime and identity theft."

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