Tachograph recorders were installed in 224 vehicles of a metropolitan police department to monitor vehicle operation in an attempt to reduce the rate of accidents. Police sergeants reviewed each tachograph chart and provided feedback to officers regarding their driving performance. Reliability checks and additional feedback procedures were implemented so that upper level supervisors monitored and controlled the performance of field sergeants. The tachograph intervention and components of the feedback system nearly eliminated personal injury accidents and sharply reduced accidents caused by officer negligence. A cost-benefit analysis revealed that the savings in vehicle repair and injury claims outweighed the equipment and operating costs.

An armed robbery alarm system was implemented in 48 different stores in two separate geographical areas for 6 months and 12 months, respectively. The alarms were placed in the two separate areas at different times and all alarms were eventually removed. Thus, multiple baseline and reversal strategies were used to evaluate program impact. A device planted in a cash drawer was triggered whenever "bait" money was removed from the drawer sending an alarm signal directly to police cars and headquarters. Onscene apprehensions of armed robbers within target stores were greatly increased even though the armed robbery systems did not deter robbery incidents nor influence the court disposition of the cases. There was also no crime deterrence, crime displacement, or increased apprehensions in either the immediate neighborhoods of target stores or on a city-wide basis. The cost effectiveness of the program was calculated to be poor even though the program is being maintained because of the absence of an alternative robbery apprehension technology.

The residential burglary deterrent effects of a helicopter patrol procedure were investigated in four separate areas with a multiple baseline technology. The helicopter was flown during an 8:00 a.m. to 4:00 p.m. period in two high density population areas of approximately 9.82 and 14.71 square miles and two low density population areas of 117.49 and 89.97 square miles. The helicopter patrol reduced residential burglaries without crime displacement in the two high density areas but had no deterrent effects in the low density areas. The costs of the helicopter patrol were justified by the benefits that resulted from the reduced home burglaries in the two high density areas. Because the helicopter patrol program is funded by general tax revenues, there is a disparity between those people paying for the procedure (all residents of Nashville) and those citizens that receive the burglary deterrent benefits (only residents of high-density areas). This distribution of benefit limitation suggests two courses of action: (1) The helicopter should be flown only in high population density areas even though the low population density areas are also victimized by high burglary rates. (2) A more comprehensive burglary reduction program must be developed so that effective deterrence can be realized in low density areas. These latter techniques would supplement helicopter patrol strategies and thus form a comprehensive burglary deterrent package that has an equitable benefit distribution.

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