Evaluating the Impact of a Specialized Domestic Violence Police Unit in Charlotte, North Carolina, 2003-2005

The specific goals of this project were (1) to assess the selection criteria used to determine the domestic violence cases for intensive intervention: what criteria are used, and what differentiates how cases are handled, (2) to track the outcomes through Charlotte-Mecklenburg Police Department (CMPD), Mecklenburg domestic violence court, and the Mecklenburg jail for the different methods of dealing with the cases, and (3) to provide an assessment of the relative effectiveness of a specialized domestic violence unit vis-a-vis normal patrol unit responses in terms of repeat calls, court processing, victim harm, and repeat arrests. The population from which the sample was selected consisted of all police complaint numbers for cases involving domestic violence (DV) in 2003. The unit of analysis was therefore the domestic violence incident. Cases were selected using a randomized stratified sample (stratifying by month) that also triple-sampled DV Unit cases, which generated 255 DV Unit cases for inclusion. The final sample therefore consists of 891 domestic violence cases, each involving one victim and one suspect. Within this final sample of cases, 25 percent were processed by the DV Unit. The data file contains data from multiple sources. Included from the police department's computerized database (KBCOPS) are variables pertaining to the nature of the crime, victim information and suspect information such as suspect and victim demographic data, victim/offender relationship, highest offense category, weapon usage, victim injury, and case disposition status. From police narratives come such variables as victim/offender relationship, weapon use (more refined than what is included in KBCOPS data), victim injury (also a more refined measure), and evidence collected. Variables from tracking data include information regarding the nature of the offense, the level/type of harm inflicted, and if the assault involved the same victim in the sample. Variables such as amount of jail time a suspect may have had, information pertaining to the court charges (as opposed to the charges at arrest) and case disposition status are included from court and jail data.

本项目的具体目标如下：（1）评估遴选家庭暴力案件以开展强化干预的遴选标准：明确所采用的具体标准，以及不同案件处理方式之间的差异；（2）通过夏洛特-梅克伦堡警察局（Charlotte-Mecklenburg Police Department, CMPD）、梅克伦堡家庭暴力法庭以及梅克伦堡监狱的相关记录，追踪各类案件处理方式对应的案件结果；（3）针对专门化家庭暴力单位与常规巡逻单位的响应效果开展相对评估，评估维度涵盖重复来电次数、法庭处理流程、受害人受伤害情况以及重复逮捕情况。

本研究的样本总体为2003年所有涉及家庭暴力（Domestic Violence, DV）的警方报案编号，分析单位为家庭暴力事件。样本采用按月份分层的随机抽样方法，同时对家庭暴力单位经办的案件进行三重抽样，最终纳入255起家庭暴力单位经办的案件。最终样本共包含891起家庭暴力案件，每起案件均涉及1名受害人和1名嫌疑人。在最终样本中，25%的案件由家庭暴力单位处理。

本数据集整合了多源数据：来自警察局计算机化数据库（KBCOPS）的变量包括犯罪性质、受害人与嫌疑人的相关信息（如双方人口统计数据、受害人与嫌疑人的关系、最高犯罪指控类别、武器使用情况、受害人受伤情况以及案件处置状态）；来自警方笔录的变量则涵盖受害人与嫌疑人的关系、武器使用情况（分类精细度高于KBCOPS数据库中的相关数据）、受害人受伤情况（同样为更精细的衡量指标）以及已收集的证据；来自追踪数据的变量包括犯罪性质、造成伤害的程度与类型，以及此次袭击是否涉及样本中的同一受害人；来自法庭与监狱数据的变量则包括嫌疑人可能被判处的监禁时长、法庭指控信息（区别于逮捕时的指控）以及案件处置状态。