Addendum: A couple of questions occurred to me. How many cops are fatally shot each year in the United States? And, how many citizens are gunned down by police? The first question was easy to answer. About 60 cops are killed by firearms each year (source). As to the other question, for some reason the powers that be don't do a good job of tracking the statistics.
This article from a few years ago provides one estimate:
Based on the data available, this most recent report suggests that the number of "justifiable" police killings has not increased since 1976, averaging 373 a year, despite a growth in both the population and the number of police officers. And while the rate at which blacks are killed by the police still far surpasses the rate at which whites are shot and killed, it has dropped to four times the white rate in 1998 compared to eight times in 1976.
While noodling around, I tried to figure out the numbers for Detroit and found some useful info.
Detroit, with nearly 1 million residents, averaged nearly 10 fatal police shootings each year between 1990 and 1998. By comparison, New York, with 7.3 million residents, averaged 28 fatal shootings a year during the same period—a rate of 0.39. |link|
Smells like a Fermi problem to me. Let's do some really simple math. Suppose that the national rate of police shootings is about half that seen in New York from 1990-1998 and that there are 300 million citizens in the United States. That would give you 585 police shootings per year. Which is a high enough number to indicate that the 373 statistic given above isn't outrageously high.
Now, I don't have any idea how many of those 373 killed were innocent of any crime, or how many had committed anything close to a capital crime. I do know that a couple of years ago the Houston Chronicle published an investigative report claiming that one in three victims of police shootings in Harris County were unarmed.
So. Police kill six citizens for every officer who is fatally shot in the line of duty, and there is good reason to believe that a significant number of those killed by police represented no threat whatsoever. Those are the facts. Call me a nut, but I think that the ideal in a democracy would be for the ratio to be skewed the other way.