Preserving American Privacy Act of 2018 This bill restricts the use of public unmanned aircraft systems (i.e., drones) to limit, to the maximum extent practicable, the disclosure of information collected by drones that is reasonably likely to enable identification of an individual or information about an individual's property that is not in plain view (covered information). The bill requires a governmental entity applying for a license to operate a drone to submit to the Department of Justice a data collection statement describing the purpose for which the drone will be used. The bill also prohibits the use of covered information collected by drones in legal proceedings and limits its use for law enforcement purposes. A governmental entity may only disclose such information for law enforcement purposes pursuant to a warrant, a court order, or in emergency circumstances. The bill prohibits: (1) the use of private drones to capture images of individuals in private activities who have a reasonable expectation of privacy, and (2) any investigative or law enforcement officer or private individual from operating a drone that is armed with a firearm.