The Trouble with Crime Statistics

​PEOPLE LOVE the seeming certainty of statistics. So when the FBI issues its Uniform Crime Report (UCR) each year, the media tells us what are the safest and least safe cities. But can the numbers really tell us that? Some criminologists say that these and other crime statistics can be misleading and should not be used blindly or exclusively to rank cities in terms of safety and crime trends.

The crime statistics are not necessarily the true measure of how much crime has been committed in a city, says Robert Brame, professor of Criminology and Criminal Justice at the University of North Carolina at Charlotte and coauthor of a new study looking at crime statistics and reporting numbers.

The researchers point out that it is unclear how many crimes are actually reported, so just looking at something like the UCR figures may be misleading. To explore that theory, they compared UCR numbers to figures in the Bureau of Justice Statistics National Crime Victimization Survey (NCVS). The latter is based on interviews with about 40,000 households that are asked about their crime experiences and whether they reported crimes.

The researchers focused specifically on burglary data for the 10 biggest cities in North Carolina. Brame says they chose burglary because it’s a crime that affects households rather than specific individuals, which is helpful because the NCVS looks at households, “so the burglary measure in the police statistics actually maps quite closely to what’s in the NCVS.” Additionally, Brame says burglary is a well-defined crime, as opposed to various types of assault, for example.

They found that even though two cities might look different in terms of what gets reported by the police department, “it’s quite plausible that their rates aren’t different at all,” he says.

For example, Brame cites the case of Charlotte and Greensboro. If you look at the raw numbers reported by the police departments, Greensboro has a higher burglary rate than does Charlotte. However, if the estimated reporting rates for the cities range from 46 to 64 percent, then the cities could actually have the same rate of burglary occurrence, says Brame, because perhaps Greensboro residents are 64 percent likely to report the crime while Charlotte residents are only 46 percent likely to report the crime.

Another factor is that the rate of crime reporting in a city can vary for different reasons. The relationship between the city residents and the police can have a big effect on the numbers reported, says David Kirk, associate professor of Sociology at The University of Texas at Austin. “If there’s mistrust of the police, individuals are less likely to think that they’re there to help and so they’re not going to report crimes,” Kirk says.

Brame notes that it is difficult to get more than an estimate for reporting rates, because while there is the NCVS, this statistic is not measured city by city. But the study shows the problems with treating these crime statistics as indisputable.

Brame would like to see the numbers presented in a different way. For example, instead of giving one number and stating it as a precise fact about the crime occurrences in a city, the authorities could report a possible range. For example, “the number of burglaries that occurred last year in Charlotte is likely between x and y.” Though that doesn’t roll off the tongue as easily as one number, Brame says it’s important to spread the idea that the other way of reporting is possibly inaccurate.

And as far as improving reporting rates, Kirk adds that there are a lot of things that police departments can do to try to improve the relationship between the police and the community. One example is community policing, he says, citing Chicago as an example of a city that improved relations between police and community. Kirk says there are other situations where the police and the community came together to solve a problem, such as a drug market intervention in High Point, North Carolina, which was a way of engaging the community in targeting low-level drug dealers. “Making the community an integral part of crime control really works well at repairing relationships between the police and the community,” says Kirk.