FBI to unlock iPhone in Arkansas case

The FBI has agreed to help an Arkansas prosecutor unlock an iPhone and iPod belonging to two teenagers accused of killing a couple, just days after the federal agency announced that it had gained access to an iPhone linked to the gunman in a mass shooting in California.

Faulkner County prosecuting attorney Cody Hiland said the FBI agreed to the request from his office and the Conway Police Department on Wednesday afternoon.

A judge on Tuesday agreed to postpone the trial of 18-year-old Hunter Drexler so that prosecutors could ask the FBI for help. Drexler's trial was moved from next week to June 27.

Drexler and 15-year-old Justin Staton are accused of killing Robert and Patricia Cogdell at their home in Conway, 48km north of Little Rock, in July. The Cogdells had raised Staton as their grandson.

The FBI announced on Monday that it had gained access to an iPhone belonging to Syed Farook, who died with his wife in a gun battle with police after they killed 14 people in San Bernardino in December.

The FBI hasn't revealed how it cracked Farook's iPhone. Authorities also haven't said whether the iPhone and iPod in the Arkansas case are the same models, or whether the FBI will use the same method to try to get into the devices.

Drexler and Staton have both pleaded not guilty to capital murder, aggravated robbery, and other charges in the deaths of the Cogdells, who were both 66.

Prosecutors have had possession of the iPhone they say belongs to Drexler since he and two other teenagers were arrested in Texas and brought back to Arkansas days after the July shootings.

Staton's defence lawyer was ordered last week to hand over the teen's iPod, which was in the defence's evidence locker.

Prosecutors said recorded phone conversations between Staton and others since his arrest indicated that he had used the iPod to communicate about the homicide plans, and that there may be other evidence on the device.

In the San Bernardino case, the US Department of Justice (DOJ) was seeking to force Apple to comply with a court order issued under the All Writs Act.

Apple said it was determined to fight the order, with senior vice president of software engineering Craig Federighi saying earlier this month that the FBI wanted to bring back the security standards of 2013.

"They have suggested that the safeguards of iOS 7 were good enough," Federighi wrote in the Washington Post. "But the security of iOS 7, while cutting-edge at the time, has since been breached by hackers. What's worse, some of their methods have been productized, and are now available for sale to attackers who are less skilled but often more malicious."

The Department of Justice struck back at such claims, stating that any impediment preventing Apple from helping the FBI was of its own making.

"This burden, which is not unreasonable, is the direct result of Apple's deliberate marketing decision to engineer its products so that the government cannot search them, even with a warrant," it said.

The DOJ said Apple's rhetoric was false and corrosive to the courts, the Fourth Amendment, and ultimately the government itself.

In a separate case, a New York magistrate judge ruled in Apple's favour when he concluded that Apple is not obligated to assist government investigators against its will.

US Magistrate Judge James Orenstein said the government put forward a reading of the All Writs Act that was so expansive as to render the Act unconstitutional.

"The government's interpretation of the breadth of authority the AWA confers on courts of limited jurisdiction thus raises serious doubts about how such a statute could withstand constitutional scrutiny under the separation-of-powers doctrine," Orenstein said.

In his judgment, Orenstein said the government was not helped in its argument by referring to another case in which the Department of Homeland Security was able to bypass passcode security to get at the data it needed.

"The government, having previously stated both that it cannot bypass an Apple's passcode security without Apple's help and that it can do so, now says that it depends -- and that what it depends on is not just which device and which operating system is in question, but also on which government expert makes the attempt," he said.

"What it does establish is simply that the government has made so many conflicting statements in the two cases as to render any single one of them unreliable."

With AAP