The Anti-Chinese riot in November of 1880 is quite a story. Denver had a section of town, populated by Chinese laborers, known as "Hop Alley". The name was in reference to the widespread use of opium amongst the "Celestials" as some people referred to the Chinese at that time. A group of railroad laborers entered a bar in the area and confronted two Chinese men playing pool, hit one of them with a cue stick, and was promptly shot at by the other pool player. He missed, but word quickly spread that a Chinaman had killed a white man. A large crowd gathered with the intent to destroy the Chinese, along with all their possessions. The eight policemen on duty were unable to control the crowd, even with the help of fire hoses. The riot continued into the night. At the time, the police were without a Chief. The City Council held an emergency meeting and appointed Dave Cook as Acting Chief. Cook had previously been City Marshal and was widely known for his bravery and intelligence. He was currently the head of the Rocky Mountain Detective Association, which was widely respected throughout the west as the premier detective agency in the area. In the meantime the riot became worse, as one of the Chinese was lynched. Cook gathered 15 of his own men, and ten others that he knew were tough gunfighters. By this time there were 2000 rioters, destroying the Chinese laundries. Cook and his men arrested nine men trying to torch one of the buildings. When the crowd attempted to free them, Cook instructed his men to fire into the ground, then aim the smoking muzzles of their guns into the rioters faces. That ploy worked well as the mob backed off. Between Cook's men, the police and sheriff's departments, and 125 special officers, the city was quiet by morning.
From A brief History of Denver Police