This report on the study first reviews the case law on the use of force by police officers, along with background information on relevant laws and standards. This is followed by an overview of previous research on the use of force by police, with attention to the strengths and weaknesses of certain types of data collection on this topic. Various types of continuum models of the use of force are discussed before the study's research design and hypotheses for the study are presented. The report then presents data from the sample of 450 incidents from Honolulu police reports, along with the results of a qualitative analysis. The study found that certain geographic areas were overrepresented in assaults on police officers, especially downtown Chinatown, Waipahu, and the west end of Waikiki. Further, certain types of incidents were more likely to result in assaults on police officers, notably incidents that involved arguments, disorderly conduct, and fights. For approximately two-thirds of the incidents, police intervention was initiated by a citizen report. Also, the study found that officers were assaulted more frequently late at night and on weekends. Another finding was that unemployed and homeless suspects were more likely to assault officers than employed residents. Other findings were as follows: suspects who assaulted officers had usually been drinking, were under the influence of drugs, or had a mental disorder; newer officers were more likely to be injured in an assault than more experienced officers; older officers were more likely to be injured in an assault than younger officers; the force used by officers corresponded to that used by suspects; officers seldom drew their guns; chemical sprays were usually effective in controlling suspects; if a crowd was present, officers were more likely to use greater force; assaults typically involved a male officer and a male suspect; and recent incidents involved more serious endangerment for officers than in prior years. 21 tables, 10 figures, 93 references, and a subject index