Police activities often come under public scrutiny when the level of force used exceeds the level considered justifiable under a given circumstance. This oftentimes skews public perceptions of police policies and procedures. Use of Force By Police: Overview of National and Local Data presents findings on the extent and nature of police use of force, discusses the difficulties in establishing measurement guidelines, illuminates circumstances under which force is applied, and provides a general framework for future research on excessive displays of force. For example, one study in this National Institute of Justice Research Report—published jointly with the Bureau of Justice Statistics—found that only 2.1 percent of 7,512 arrests involved the use of weapons by police.