Laws bearing upon the operation of the criminal justice system are typically narrow in focus, designed to impact on only one component of the entire system. Also, the criminal justice system is complex, with a high degree of interrelatedness among components. The system's tendency to maintain an overall balance activates all the components of the system to act to negate either the direct adoption of the law or its intended consequence. An example of a change in law intended to impact on one component of a system to ultimately affect another part of the system is Michigan's 'Proposal B,' a constitutional amendment which states that convicted felons must serve at least the minimum prison sentence without reduction by 'good time.' Previously, most inmates were eligible for parole before the minimum sentence was served on the basis of good behavior in prison. Research currently underway to measure the impact of this legislation is designed to measure (1) the criminal justice system response to the new policy, (2) the effect of the new policy on the prison population, (3) whether the policy reduces the crime rate and increases the incapacitation effect, (4) any deterrent effect, and (5) the effect of inmate behavior. Data are being collected for crime rates, arrest rates, offender plea alternatives, conviction rates, length of sentence, prison population, judicial decisionmaking, and critical inmate incidents. Fifteen references are provided.