The United States Department of Justice has filed its latest response to Apple in the legal fight over iPhone encryption.
In the document, filed today, the DOJ wrote: "Here, Apple deliberately raised technological barriers that now stand between a lawful warrant and an iPhone containing evidence related to the terrorist mass murder of 14 Americans.
"Apple alone can remove those barriers so that the FBI can search the phone, and it can do so without undue burden.”
The filing, published by CNBC, is the latest development in an argument over whether Apple should help authorities unlock an iPhone that was used by one of the shooter is last year’s San Bernardino attack, which left 14 people dead.
Apple refused to back down last month, saying in a statement: "We feel the best way forward would be for the government to withdraw its demands under the All Writs Act and, as some in Congress have proposed, form a commission or other panel of experts on intelligence, technology, and civil liberties to discuss the implications for law enforcement, national security, privacy, and personal freedoms. Apple would gladly participate in such an effort."
The DOJ described the court order to unlock the phone as “modest” and argued it “invades no one’s privacy”.
The filing also suggested Apple makes "special accommodations in China" and questioned the tech company's assertion that if the US court rules in favour of the FBI it would cease to resist other governments' efforts to obtain iPhone information.
The filing said: "It offers no evidence for this proposition, and the evidence in the public record raises questions whether it is even resisting foreign governments now.
"For example, according to Apple’s own data, China demanded information from Apple regarding over 4,000 iPhones in the first half of 2015, and Apple produced data 74% of the time."
The tech giant is due to face the FBI in court this month.
City A.M. has asked Apple for comment.