Wednesday, April 11, 2012

Deconstructing data on police deaths

Okay, here's a strange one. The headline in the New York Times Monday read: "Even as Violent Crime Falls, Killing of Officers Rises," reporting "a 25 percent increase" in 2011 in police officer homicides "and a 75 percent increase from 2008. Startling data, huh? But the truth is more complex. While police officer deaths did rise in 2011, they've also dramatically declined so far in 2012, as Radley Balko pointed out over the weekend. Here are the data for 2012 so far compared to last year via the National Law Enforcement Officers Memorial Fund:

Law Enforcement Officer Fatalities
Preliminary 2012 Numbers
April 11, 2012

2012 2011 % Change
Total Fatalities 31 59 -47%
Firearms-related 11 26 -58%
Traffic-related 12 19 -37%
Other Causes 8 14 -43%

Why wasn't THAT the news hook? Such preliminary data were good enough to hype last year. IMO the answer is that sensationalistic bad news draws more readers than stories about positive trends. Journalists have a natural schadenfreude that encourages them to frame stories in the most alarming ways, but good news travels slowly, even during the 24-hour news cycle.

In this case, the Times also cherrypicked the data a bit. Dating the 75% increase from 2008 obscures the fact that on-the-job officer deaths were much higher in 2007, when 189 officers died on the job compared to 141 in 2008. This graph depicting the long-term pattern on officer deaths shows the recent "trend" hyped by the Times is really more a regression to the mean:

Police Officer Deaths in the Line of Duty, 1961-2011


So the tendency analyzed in the Times is a bit of a construct. Reporters could just as easily have said the total number of police officer deaths declined 8.5% compared to 2007, but would Times editors have considered that news "fit to print"?

In addition, limiting their stat to police homicides ignores most on-the-job police deaths, which much more frequently happen because of accidents, often in traffic. In 2010, for example, 153 officers died on the job nationwide, but the FBI data on which the NY Times based its analysis counted 56 officers "feloniously killed" that year. So when calculating the increase in the Times story, most on-the-job police deaths weren't counted.

Anytime you're analyzing statistics involving such small numbers, special care is warranted. With more than 700,000 sworn officers in the United States, these small fluctuations are not necessarily statistically significant. Notably absent from the Times story was any analysis by a statistician on whether these short-term data fluctuations are meaningful. Instead, the article is filled with speculation about the reasons for a trend that may or may not exist.

Being a police officer is not remotely the most dangerous job out there, nor even the most dangerous government work. Excluding soldiers who die in combat, garbage collectors rank highest among government workers in the likelihood they'll be killed on the job. The people picking up your trash put their lives on the line every day and are more likely not to make it home at night than their brethren in blue. But one suspects we won't any time soon see a New York Times headline memorializing their sacrifice.

16 comments:

Anonymous said...

I sure hope you're just as willing to critically analyze the "data" coming out here lately regarding instances of "prosecutor misconduct." We sure wouldn't want anyone to believe there's a double standard here, would we?

Gritsforbreakfast said...

The difference is these data are unambiguously comprehensive. It's actually possible to know how many police officers die on the job. There is no way to accurately identify how much prosecutor misconduct is out there.

All we can definitively say about prosecutor misconduct is that when it occurs, it is not punished. The data cannot tell us how often it occurs, and this writer has never claimed it does.

Anonymous said...

Given your hundreds of malevolent comments about the police, maybe we should look elsewhere for factual or unbiased information. It's easy to make statistics say what you want them to say.

RAS said...

Perhaps their data manipulation is to take the heat off Obama over 'fast and furious' or just another deceitful attempt to justify gun control.

Anonymous said...

Grits,

The 700,000 LE positions identified by the FBI doesn't, I believe, include the 100,000 plus (150,000-200,000?) federal law enforcement personnel.:~)

Anonymous said...

Anon 5:35,

What do you think the statistics say? Hell of a lot more dangerous to be a pilot than a cop. Just easier to get injured, not killed, as a cop.

DougD said...

Yet another attempt to skew the facts and minimize the minimize the dangers faced by the police. You need to put things in their proper context, Grits. It's not just about raw statistics. It's about on-the-job murder. It's about being assaulted at work by your "customers." It's about using better equipment and training to prevent or mitigate the assaults and attempted murders of police that occur with increasing regularity. The stats on officers killed do not even begin to tell the story about the dangers inherent to the job.

Gritsforbreakfast said...

DougD says, "The stats on officers killed do not even begin to tell the story about the dangers inherent to the job."

I suppose that may be true if we disassociate the word "danger" from "risk of death." If we factor in the latter, though, garbage collectors jobs are more "dangerous," and fishermen, loggers, etc.. It doesn't disrespect you to point out that other people take greater day-to-day risks on their jobs.

As for 5:35 referencing my "hundreds of malevolent comments about the police," please identify one so I'll know what you're talking about. I've received a few malevolent comments FROM police over the years, but don't recall any ABOUT them.

Anonymous said...

Want to talk about being assaulted at work by your "customers" DougD? The most dangerous job in America is prostitution.

http://skeptifem.blogspot.com/2010/08/most-dangerous-jobs.html

Anonymous said...

DougD,

Assaulted at work by customers? Simply look at all the convenience store workers' murders. Sorry Doug, but trying to frame officer deaths as being "special" in and of it self simply reflects a victim mentality. I remember when a combat vet complained that some civilian who had suffered through a major trauma and was later identified as having Post Traumatic Stress Syndrome shouldn't be allowed to have that diagnosis as it would detract (and cheapen) the anguish that servicemen suffered through. He was as wrong as you are.:~)

Tina Trent said...

Huh.

It's a cold day in hell for me to side with the Times' reporting.

But you're either intentionally misapprehending the subject of the article, or you swallowed your magic statistical decoder ring in your grits this morning.

I bet, malice. Because this isn't very hard to understand, and you're a professional anti-police activist, though it is stooping pretty low to fudge numbers in order to justify a whinge about murdered police being post-humously coddled by people who care too much when they're dead.

The Times article was about killings of police officers by perpetrators, not overall deaths on the job -- and killings have gone up.

"72 officers were killed by perpetrators in 2011, a 25 percent increase from the previous year and a 75 percent increase from 2008. The 2011 deaths were the first time that more officers were killed by suspects than car accidents."

"The number was the highest in nearly two decades, excluding those who died in the Sept. 11 attacks in 2001 and the Oklahoma City bombing in 1995."

And then they show you that helpful little chart. The one with the line that rises going left-to-right (excluding Sept. 11).

The rest of the article reasonably examines the techniques being employed to try to mitigate murders of police in 2012.

It does not discuss traffic accidents involving sanitation workers, which appears to be your primary ethical complaint.

So the real question is: why would you assume that your readers are stupid enough to fall for such blatant misdirection?

I imagine THAT chart has one side labelled "seething resentment towards police" and, on the perpendicular, "what I can get away with."

And, regarding your equally disingenuous request for instances of your anti-cop hostility, here's one (you're the one doing the speaking): "Grits has been a bit of a thorn in the department's side dating to the mid-'90s when I co-founded a political action committee that successfully pushed for the creation of Austin's Police Monitor Office and ran a website publishing police misconduct reports from the department garnered under open records. . .
Did I intentionally make up the drawn taser? Of course not, no more than a witness who falsely identifies a suspect by mistake. In 2001, I helped pass the legislation to require cameras in police cars, for heaven's sake, I knew full well the incident was being taped! I said what I remembered and remembered that detail wrong."

Detail? That's a pretty lame attempt to make an excuse for doing something really malevolent to an innocent officer.

Gritsforbreakfast said...

Tina, last year the preliminary data from the National Law Enforcement Officers Memorial Fund was the source of massive MSM hype led by Eric Holder about a rise in officer deaths. This year when the same data shows the opposite trend, the media ignore that data and focus instead on a smaller subset of police deaths to claim the job is still getting much more dangerous.

In other words, whichever direction the trend goes, up or down, the media portrays the job in a way that maximizes anxiety over police deaths, when in reality they're less common than in other dangerous occupations.

Finally, admitting I've sometimes been a "thorn in the side" of Austin police in a watchdog role is hardly the same as overt "malevolence." The examples you cite don't remotely support that claim, and I again defy you to identify any openly malevolent comments toward police on Grits. Search as long as you like, you just won't find them. That's you projecting your biases, not an accurate depiction of what's really written here.

A Texas PO said...

From the comments above, I can understand what is being said on both sides. But what I am understanding from this is that there's a huge distinction between being killed in an "accident" at work (the way most sanitation workers are) and being murdered by a perp on the job. Now, as a professor in graduate school always told me, "Always assume the data and charts you're being shown are hiding something important before taking it at face value." I see how that might be the case here. But being that Ofc. Jaime Padron was just buried in Austin and many hundreds came out to pay their respects to him, I can see how this can be a bit of a sore subject in Austin. Rest in love, Ofc. Padron!

Anonymous said...

RE: A Texas PO,

I'm sure that Grits' decision to address this specific issue immediately after the murder of an Austin police officer was pure coincidence. He was merely commenting on a NY Times article and never thought for a moment that his timing might seem either thoughtless or malevolent. If Officer Padron were still here, I'm sure he would agree with Grits and Balko about the silly suggestions that being a cop is any more dangerous than any other job.

Anonymous said...

This seems like it was a bit of a pointless post. Yes, there are other dangerous professions. For instance, whenever there's s mining accident, we see news stories about the dangers miners face. I doubt that Grits follows up after those with posts about how the country should stop worrying about miners and turn it's attention to fishermen and garbage collectors instead. (For that matter, Grits is very concerned -- and rightfully so -- about the possibility that there might have been a very small number of wrongfully executed people in the U.S. in the past 3 decades. It would be a pretty stupid response for some one to say that Grits should be worrying about bathtub slip and fall deaths instead.)

From my perspective, as a citizen, I see policing as z dangerous and stressful job that has helped me directly (by preventing me from being victimized) and has helped a huge number of people who are more vulnerable than me (children whose abuse they stop, for instance). When a police officer dies in the line of duty -- as happened this week in New Hampshire and in central California, I see it as a tragedy giving reason to reflect on the gratitude I owe them.

Gritsforbreakfast said...

11:48 et. al., my prayers go out to Officer Padron's family and this post was certainly not focused on that or any other particular case. Instead it reacted to a statistical analysis in the New York Times, which I do not believe timed the story to coincide with the local incident. Neither did I. Of course, even the local coverage makes the same point as this post, but I don't consider the Statesman anti-cop for reporting this was the first shooting of an Austin police officer in 35 years. Facts are facts, just like the federal data about on-the-job deaths. I both mourn what happened to Ofc. Padron and am grateful such incidents are relatively uncommon.