Mayor Mike Johnston and Denver public safety leaders gathered at City Hall on Monday to reject a U.S. Department of Justice demand to repeal the city’s longstanding ban on assault weapons. “Our first job is to keep Denverites safe, and we will not be intimidated out of doing it,” Johnston said. “Denver’s law has stood for 37 years because it works, it saves lives, and it reflects the values of our community. No demand or lawsuit from Washington is going to change that.” The demand, which arrived in the form of a letter from the DOJ, threatens a lawsuit if Denver does not comply.…