Hi there. I understand that effective evaluation of community corrections programs is critical if we are to begin to understand what treatments are capable of producing lasting change in offenders. However, I am not sure if it is necessary for us to try experimental design since it sounds not a social worker style…

No problem.

Thank you for the detailed reply.

One investigative technique that provides the analyst maximum control, so that the relationship between a particular element of a project and the desired outcome can be isolated from other causal forces and measured accurately, is the laboratory experiment. If all factors are held constant, and an effect is observed after one-factor changes, the researcher is in the strongest position to say that the manipulated factor caused the observed effect. Branches of science that have been able to impose laboratory conditions upon the matters they investigate have thus developed powerful explanations for complex phenomena. In the field, however, such control over subjects and their environments are not gainable. The strategy for approximating this control is to assign at random equally eligible subjects (cases, arrestees, addicts, and so forth) to two groups. The subjects in one group (the “experimental group”) are then exposed to or given the “treatment”—be it a drug treatment project, enhanced prosecution, or whatever else the project is designed to do—while the other group (the “control group”) is not. The random assignment provides optimal assurance that any differences in the outcomes observed in the two groups are attributable to the experimental treatment, and not to preexisting differences or to chance. While it may seem difficult to undertake experiments in criminal justice settings, several studies with experimental designs have been carried out with much success, yielding powerful findings. Unfortunately, such studies are complicated, often vulnerable to some threats that may spoil the ability to draw strong conclusions, and generally very costly and time-consuming.