Violent Illumination

OnAugust 13, 1906, the town of Brownsville, Texas was in chaos. A shooting that night left a white bartender dead and a white police officer wounded. The townspeople, already on edge due to the alleged attack of a white woman the previous evening, pointed all blame at the 25th Infantry Regiment stationed at nearby Fort Brown. The 167-member troop, an allBlack regiment, had arrived just over two weeks prior. At the center of the case was eyewitness testimony. Several residents testified that they saw between 5 and 12 African American men shooting in the streets or sprinting away after the crime. Though the night was dark, they testified that they could make out the men’s skin color and distinctive khaki uniform by the light of nearby street lamps. One man, named Mr. Rendall, testified that he saw eight men jump a wall in escape from a distance of about 150 feet. Another said that the street lamp cast a radius of about 20 feet, and in that distance, he saw the Black men retreat. The accused Black soldiers denied all charges, and no single man was ever indicted for the crime. Even so, President Theodore Roosevelt responded by dishonorably discharging the regiment. Over the course of the following year, the Senate Military Affairs Committee investigated what happened that night in Brownsville. Investigators wanted to know whether a person could tell a man’s skin color by the light of a street lamp on a city street shrouded in darkness. So they conducted an experiment. They had African American, white, and Mexican men pass beneath street lamps of similar candlepower on a similarly starlit night from varying distances, and they tested whether observers could determine the men’s skin color. Lieutenant Robert P. Harbold, who ran the experiment, had men pass him and other officers from a distance of 25 feet, with a “light shining brightly about 10 or fifteen feet beyond the squad, so the men were between the officers and the light.” Harbold quickly made a discovery: