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What are the limitations on the data on gun ownership, gun usage and crime?
A 2005 data review done by a panel of criminologists, statisticians, and epidemiologists for the National Research Council concluded that there is a lack of reliable data and “in some instances—firearms violence prevention, for example—there are no data at all.”
The NRC report said that “none of the existing data sources, by itself or in combination with others, provides comprehensive, timely, and accurate data needed to answer many important questions pertaining to the role of firearms in violent events.”
The panel reported that “even some of the most basic descriptive questions cannot be answered with existing data.” It cited such unanswered questions as:
• What proportion of suicide or homicide victims were under the care of a mental health professional? What proportion of those victims were intoxicated at the time of death?
• In what proportion of spouse or intimate-partner homicides committed with a gun does the offender take his own life or the lives of the victim’s children or protectors?
• Did the number of people shot with “assault weapons” change after Congress enacted the 1994 ban on certain types of such weapons?