Monday, September 28, 2009

Too little data to draw conclusions about spike in Houston police shootings

One of my all-time favorite lines from a Simpsons episode came at the abrupt end of a chaotic story when the family tried to discern what the "moral" to it all was. Finally, Lisa suggested, "Perhaps there is no moral to the story," to which Homer eagerly agreed, replying it was "just a bunch of stuff that happened."

That bit of wisdom came to mind when I was reading Jim Pinkerton's story from the Houston Chronicle, "More people shot by Harris officers" (Sept. 28), presenting various (mostly self-interested) explanations for why Harris County saw a jump in the number of police shootings and death at the hands of police officers last year. There were a long list of people quoted in the article looking to find the story's moral:

The police union blames the economy, but also says it's because officers aren't getting enough overtime opportunities and also that, "This state, and the country, does a terrible job of taking care of the mentally ill." Activist Quanell X said too many of those shot were unarmed (the story contained no data one way or the other about that). The Harris County DA blamed new laws allowing more citizens to legally carry firearms. (No data to support that, either.) The president of the Harris County Criminal Lawyers Association "wondered if the shootings are a lingering effect from police confrontations with criminals mixed with the wave of Hurricane Katrina refugees."

There's really no evidence presented to support any of these theories, which is why personally I'm inclined to agree with the Sam Houston State professor quoted who thought it was too early to draw any hard conclusions:

One criminal justice expert said the increase is not significant, adding that alarms should sound only if the numbers climb steadily upward for another two years.

“You've got ... a short-term random fluctuation,“ said Larry Hoover, professor of Criminal Justice at Sam Houston State University, and director of the Police Research Center. “I don't think there's been any social, demographic, economic or crime change that explains the increase.”

Hoover noted that “overall, homicide rates fluctuate fairly broadly in a given jurisdiction, and it should come as no surprise that police-related shootings might do the same by chance circumstance.”

The problem is we're talking about really small numbers of total fatal shootings so even single-digit fluctuations appear statistically large, even if they may not be statistically significant. IMO it'd be wrong to assume this one-year spike represents a meaningful trend, but at the same time it'd be wrong to consider last year's number of fatal shootings some sort of goal or baseline. As the police union boss told the paper, “In law enforcement, we never want to discharge our weapon. But when we have to, it's inevitable that it's life or death ... I'd like it to be zero.”

Certainly, it'd be useful to answer some of the questions raised by those speculating in the story. Were there more unarmed people shot than usual? Were more of those shot legally carrying weapons, as the DA claims? Were there instances where not enough officers were on the scene because of understaffing, or where the person shot was in a mental health crisis? And how would those breakdowns come out applied to the last several years?

That information is for the most part knowable through public records, though it takes a lot of legwork to get at it and police departments are (regrettably) loathe to do it proactively. In Austin the American-Statesman at one point undertook an extensive analysis of use of force incidents in the capital that tried to answer some of those questions (though it didn't win them any popularity contests among officers). But you couldn't conclude too much from the topline data and off-the-cuff speculation presented in this article. Perhaps there is no moral. It could be just a bunch of stuff that happened.

1 comment:

Anonymous said...

More officer involved shootings because they don't get enough OT? What?
More shootings because more lawful citizens carry? What?
My intelligence is insulted and if the utterers of these remarks carry badges, I'd like them dismissed, never again to carry a badge, immediately.