What do clearance statistics count?
Clearance statistics measurethe proportion of reported crimes that were resolved by an arrest or other, exceptional means (e.g., death of the offender, unwillingness of the victim to cooperate). A single arrest may result in many clearances. For example, one arrest could clear 40 burglaries if the person was charged with committing all 40 of these crimes. Or multiple arrests may result in a single clearance if the crime was committed by a group of offenders. For those interested in juvenile justice issues, the FBI also reports information on the proportion of clearances that were cleared by the arrest of persons under age 18. This statistic is a better indicator of the proportion of crime committed by this age group than is the arrest proportion, although there are some concerns that even the clearance statistic overestimates the juvenile proportion of crimes.
For example, the FBI reports that persons under age 18 accounted for 30% of all robbery arrests but only 17% of all robberies that were cleared in 1997. If it can be assumed that offender characteristics of cleared robberies are similar to those of robberies that were not cleared, then it would be appropriate to conclude that persons under age 18 were responsible for 17% of all robberies in 1997. However, the offender characteristics of cleared and noncleared robberies may differ for a number of reasons. If, for example, juvenile robbers were more easily apprehended than adult robbers, the proportion of robberies cleared by the arrest of persons under age 18 would overestimate the juvenile responsibility for all robberies. To add to the difficulty in interpreting clearance tatistics, the FBI's reporting guidelines require the clearance to be tied to the oldest offender in the group if more than one person is arrested for a crime.
In summary, while the interpretation of reported clearance proportions is not straightforward, these data are the closest measure generally available of the proportion of crime known to law enforcement that is attributed to persons under age 18. These data should provide a barometer of the changing contribution of persons under age 18 to the Nation's crime problems.