Alina Selyukh writes: “The Department of Justice has filed a motion to compel Apple to cooperate with a government investigation and help access data on an iPhone used by one of the San Bernardino assailants. The motion filed in the U.S. District Court for the Central District of California (read it in full below) lays out the government’s legal case for why Apple should provide technical assistance. It could be viewed as a response to Apple’s open letter this week stating why the company is refusing to assist — as well as a preemptive move by the prosecutors ahead of Apple’s own court filings expected next week. (Click here for our comprehensive explainer on what’s going on, and here for other NPR coverage on the standoff so far. As a very quick recap: The government had earlier gotten a court order directing Apple to create special software that would help investigators crack the phone’s PIN code. Apple CEO Tim Cook’s letter argued this would set a dangerous precedent and could undermine the security of all iPhones)…”