A specific field in which statistics is used is the field of crime. IN this post, we will look at how researchers attempt to measure crime. Primarily we will look at issues with data collection and one of the main agencies for consolidating data regarding crime.
Data Collection
A major challenge in measuring crime is that not all crimes are reported. It is common for rape victims to avoid reporting what happened to them. Criminals are also usually reluctant to report crimes that happen to them. Petty and property crimes are also underreported. As such, the collected data does not fully represent crime in the actual world.
One source for criminal statistics is the Uniform Crime Report (UCR). Compiled by the FBI since 1930, the UCR gathers data from over 90% of all of the various police agencies in the USA. This report contains data from Part 1 crimes, which are generally serious crimes, including some of the following.
- Murder, manslaughter
- Forcible rape
- Robbery, burglary
- Arson
- Various forms of theft (larceny, motor vehicle)
- Gambling
Another hurdle to crime reporting to the UCR is that each agency must report the most single crime for each instance of criminal activity. For example, if multiple crimes are committed by one person in one instance, only the most serious offense is reported.
Arrests are also reported to the UCR. Collecting data on arrests helps agencies calculate a clearance rate and the percentage of crimes that lead to an arrest.
There can also be issues after a criminal is caught and does time. FOr example, in one county, a juvenile may commit a crime and get probation, but in another county, they may have to do time behind bars. This is partly due to various philosophies of judges and probation officers in dealing with crime. This makes a difference in criminal punishment based on philosophy rather than something less subjective.
Consumers of Crime Statistics
Policymakers often use the collection of criminal statistics to determine various laws and funding they want to provide to law enforcement agencies. One common problem is that consumers of crime statistics are not aware of the context in which the data is collected, leading to faulty conclusions.
For example, back in the 1990s, there was a dip in criminal behavior. A group of experts concluded that this dip in criminal behavior was due to changes in access to birth control in the 1970s. The thinking went that the birth of unwanted children in the 1970s prevented the birth of criminals who would have been terrorizing society in the 1990s.
The example above may be considered an extreme example, but this can happen when people place their interpretation on data without having a deeper understanding of how that data was collected. Given that crime statistics are not 100% reliable, strong conclusions should be guarded.
Conclusion
Despite these challenges, data on crime is needed. What is really important is that people avoid jumping to strong conclusions based on data known to have issues. Some insight into criminal behavior is better than none, but care and restraint are needed in the conclusions.