The Uniform Crime Reports (UCR) compile data from over 17,000 law enforcement agencies across the country. They provide detailed data regarding the volume of crimes to include arrest, clearance (or closing a case), and law enforcement officer information. The UCR focuses its data collection on violent crimes, hate crimes, and property crimes. Created in the 1920s, the UCR system has not proven to be as uniform as its name implies. The UCR data only reflect the most serious offense in the case of connected crimes and has a very restrictive definition of rape. Since about 93% of the data submitted to the FBI is in this format, the UCR stands out as the publication of choice as most states require law enforcement agencies to submit this data.
Preliminary Annual Uniform Crime Report for 2005 was released on June 16, 2006. The report shows violent crime offenses rose 2.5%, but the number of property crime offenses decreased 1.6% compared to 2004.
The National Incident Based Reporting System (NIBRS) crime statistics system aims to address limitations inherent in UCR data. The system used by law enforcement agencies in the United States for collecting and reporting data on crimes. Local, state, and federal agencies generate NIBRS data from their records management systems. Data is collected on every incident and arrest in the Group A offense category. The Group A offenses are comprised of 46 specific crimes grouped in 22 offense categories. Specific facts about these offenses are gathered and reported in the NIBRS system. In addition to the Group A offenses, eleven Group B offenses are reported with only the arrest information. The NIBRS system is in greater detail than the summary-based UCR system. As of 2004, 5,271 law enforcement agencies submitted NIBRS data. That amount represents 20% of the United States population and 16% of the crime statistics data collected by the FBI.
Preliminary figures indicate that, as a whole, law enforcement agencies throughout the Nation reported an increase of 1.3 percent in the number of violent crimes brought to their attention in 2006 when compared to figures reported for 2005. The violent crime category includes murder, forcible rape, robbery, and aggravated assault. The number of property crimes in the United States from January to December of 2006 decreased -2.9 percent when compared to data from the same time period in 2005. Property crimes include burglary, larceny-theft, and motor vehicle theft. Arson is also a property crime, but data for arson are not included in property crime totals. Figures for 2006 indicate that arson increased 1.8 percent when compared to 2005 figures for the same time period.