THE KANSAS CITY PREVENTIVE PATROL EXPERIMENT 堪薩斯城巡邏實驗

     The experiment involved variations in
the level of routine preventive patrol within 15 Kansas City police beats. These beats were
randomly divided into three groups. In five “reactive” beats, routine
preventive patrol was eliminated and officers were instructed to respond only
to calls for service. In five “control beats”, routine preventive patrol was
maintained at its usual level of one car per beat. In the remaining five “proactive”
beats, routine preventive patrol was intensified by two to three times its
usual level through the assignment of additional patrol cars and through the
frequent presence of cars from the “reactive beats”

     The experiment found that the three
experimental patrol conditions appeared not to affect crime, service delivery
and citizen feelings of security in ways the public and the police often assume
they do. For example,

◎    as revealed in the victimization survey , the experimental conditions
had no significant effect on residence and non-residence burglaries , auto
thefts, larcenies involving auto accessories, robberies, or vandalism-crime traditionally
considered to be deterrable through preventive patrol；

◎    few significant difference and no
consistent pattern of differences occurred across experimental conditions
in terms of citizen attitudes toward police services;

◎    experimental conditions did not
appear to affect significantly citizen satisfaction with the police as a result
of their encounters with police officers.

 

     此實驗變數為15個堪薩斯城警方例行的預防性巡邏的區域。這15個巡區被隨機分成三組。 在其中5個以被動(reactive)方式的巡邏區，例行的預防性巡邏是被移除的並執行員警也被指導僅只要對要求的報案作處理。在五個控制組(control)的巡邏區，例行的預防性巡邏被執行以一個巡區配置一台警車巡邏的慣例。
在餘下的五個主動式(proactive)的巡邏區，透過額外的巡邏警車任務以及從被動式巡區調來的警車頻繁巡邏，加強了原先例行的預防性巡邏其慣例的標準2到3倍。

     但實驗發現，三個實驗巡邏條件似乎不如大眾與警方假設其作為會影響到犯罪的發生，警力服務的提供和市民的安全感這些方面。
例如，

◎
在受害情況調查顯示，實驗條件下傳統認為對於透過預防性巡邏居住和非居住爆竊，汽車竊盜，汽車配件的竊盜，搶劫或破壞公物的犯罪會有遏止性效果但其發現卻是沒有任何顯著影響，  

◎
在市民對警力服務的態度上幾乎無顯著的差異，且在交互實驗狀況下並沒有任何前後一致差異的模組發生;

◎ 實驗條件並未出現市民對於與警方的來往滿意度上有顯著的影響。