Statistics can promote a healthier dialogue between “black” African-American communities and “blue” uniformed police. When combined with basic principles of statistical inference, they provide insights into the likely apprehensions on each side. They also point to more effective ways to reduce violence without compromising public safety or private liberty.
Let’s start by looking at the data. The FBI’s Uniform Crime Statistics reports that on-duty police over the past decade killed about 4,000 people, an average of 400 a year, of which a third were black or African-American. However, police reporting to the FBI is neither mandatory nor uniform. After surveying major police departments, reporters from The Wall Street Journal estimated that the true number is about 50% higher. Some informal monitoring groups suggest the true number is closer to 1,000 a year.
As a benchmark I will estimate 800 police killings a year, which doubles the FBI estimate and is midway between the WSJ and monitoring estimates. As a benchmark I’ll also assume that the racial breakdown of the 800 matches the breakdown in the FBI data. That works out to approximately 270 African-Americans killed each year by on-duty police.