By Dan Schroeder
After complaining loudly about the recent Standard-Examiner article on crime statistics, I think I owe it to readers to show what a competent handling of the statistics might look like.
Crime statistics for 2008 are not yet officially published, and it's impossible to interpret the bits and pieces provided in the recent news article. However, as reported a couple of months ago, we now have published data for all of 2007.
So I've added this to the earlier data that was analyzed on this blog last year, and produced some new graphs.
The first graph shows the total number of violent crimes (homicides, rapes, robberies, and aggravated assaults) reported in Ogden each year:
The second graph shows the total number of crimes reported in Ogden each year that fall under the Uniform Crime Reporting (UCR) categories. These include the four categories of violent crimes plus burglary, larceny, auto theft, and arson:
Here the BCI data again show a disturbing upward trend for the last two years, while the FBI data indicate almost no change since 1999.
For those interested in the details, there's plenty more to say...
• These statistics don't include all crimes. Notably absent are simple assaults, fraud, forgery, drug offenses, traffic violations, and a number of less common types of crimes. However, for historical reasons, the eight UCR crime categories are the ones for which the best data are available.
• These graphs simply show the number of crimes--not the crime rate, which is the number of crimes per person. I've done this because you can't calculate the crime rate unless you have accurate population data, and there seems to be no agreement on how Ogden's population has changed between census years.
If we assume that Ogden's population has increased gradually over the time period shown, then graphs of the crime rates would be tipped somewhat more downward (or less upward).
• The graphs that the city (and the Godfrey campaign) published last year were of the crime rates. But these graphs used the 1990 census figure (about 63,900) for Ogden's population through 1999, then used the 2000 census figure (about 77,200) for the population thereafter. Unless you believe that Ogden's population increased by 21% in a single year, this trick created an apparent, but mostly artificial, 21% drop in the crime rates between 1999 and 2000. Conveniently, 2000 was the year that Mayor Godfrey took office.
• The three data sets for the number of UCR crimes (violent or total) should all agree with each other, because they ultimately come from the same source. The Ogden City Police Department collects the data and transmits it to the Utah BCI, which in turn transmits it to the FBI. It's therefore puzzling to see significant differences between the three data sets in recent years.
• The discrepancies between the FBI and BCI data sets may have something to do with the timing of their reports, and the fact that the city can provide updates and corrections to the data as much as a year after it is first transmitted. Last fall I contacted the BCI directly and learned that their latest data for 2006 were in agreement with the FBI's lower numbers, even though the report on the BCI web site contained (and still contains) the higher numbers. It should also be mentioned that the 2007 BCI data are still labeled "preliminary"; their final report won't be published until next month.
• The Godfrey administration's still-lower numbers for 2005 and 2006 also beg for explanation. Some possible clues can be found in the administration's breakdown by specific crime categories, which shows a precipitous decline from 107 robberies in 2004 to only 35 in 2005, and a decline from 849 burglaries in 2004 to only 520 in 2005. Both of these declines seem implausible because there were no such dramatic fluctuations in the previous 12 years, and because neither decline is reflected in the BCI or FBI data. However, the headings in the administration's table are "Robbery/Weapon" and "Burglary/Residential", which may indicate that "strong arm" robberies and nonresidential burglaries are excluded. Such exclusions would be in clear violation of the FBI's UCR standards, and it would be especially misleading to include these crimes up to 2004 but exclude them from 2005 on. Still, although it's impossible to be certain, I'm guessing that this is what the Godfrey administration has done.
• It should be noted that the table on the Ogden City site was posted there on 23 October 2007, the same day that a guest commentary by Jim Hutchins on this subject was printed in the Standard-Examiner. However, graphs and summaries of the same data had already been published in a city-sponsored newspaper ad, in a utility bill insert, and on Mayor Godfrey's campaign web site. The city has been asked (via written GRAMA request) to provide an even more detailed breakdown of the data for recent years, but has refused.
• During his campaign last year, Mayor Godfrey repeatedly claimed credit for reducing Ogden's total crime rate by 23%, and for reducing Ogden's violent crime rate by 43%. The truth is that both the total crime rate and the violent crime rate have been approximately flat since Godfrey first took office. After the errors in the administration's methodology have been corrected, any remaining changes since 1999 are small compared to the uncertainties due to differing data sets, the lack of good population data, and the random fluctuations that one would expect from year to year.
• The July 25 Standard-Examiner article was deficient in several ways. The text of the article reported that robberies and aggravated assaults increased by 19% from 2006 to 2007, even though the raw data (provided in an accompanying table) indicate an increase of 24%. More importantly, the text of the article failed to point out that this increase fell on top of similar increases in violent crime during the previous two years, resulting in a total violent crime increase of 64% since 2004 (according to the BCI data). This article was based entirely on the BCI data, with no indication that other sources (the FBI and the Godfrey administration) might differ. The graph accompanying the article didn't even include the new 2007 data, presumably because the preliminary BCI report didn't provide a population figure from which one could compute the crime rate. And finally, the article quoted Mayor Godfrey saying he actually knew the 2007 crime statistics would be higher and "attempted to communicate [this] to everyone a year ago," with no attempt (on the part of the newspaper) to verify whether there ever was such a communication and no mention of the multiple communications that the Godfrey administration and campaign sent out last year, claiming that the crime rates had dropped by large percentages.
• The September 15 Standard-Examiner article was even worse, because it labeled the data in a way that's impossible to interpret, and because the newspaper obviously allowed the city to cherry-pick the exact data (from a particular neighborhood, during a particular time period) that it wanted released.
• Ultimately, none of this data is any better than the methodology used to collect it. Even those of us who have never attended a crime conference can easily imagine that minor differences in protocol and classification of crimes might create noticeable differences in the statistics. There could also be inconsistencies from year to year in the fraction of crimes that get reported to police. And finally, as was pointed out by Professor Wadman in the recent news article, the underlying causes behind rising and falling crime statistics are extremely complex. So in the end, Ogden's crime statistics don't show any discernible trends that can reasonably be blamed on (or credited to) Mayor Godfrey or anyone else.
It's quite clear, however, that the mayor has made a practice of distorting and politicizing crime statistics for his personal benefit.