The FBI–Apple encryption dispute concerns whether and to what extent courts in the United States can compel manufacturers to assist in unlocking cell phones whose data are cryptographically protected. There is much debate over public access to strong encryption. In another case in Brooklyn, a magistrate judge ruled that the All Writs Act could not be used to compel Apple to unlock an iPhone. The government appealed the ruling, but then dropped the case on April 22, 2016, after it was given the correct passcode.