ing a new program. In other contexts, however, Congress uses a "stick," withholding funding for ongoing federally supported state activities, such as highway construction. For example, a provision of the National Highway System Act of 1995 directed the Department of Transportation to withhold federal highway construction monies from states that failed to enact "zero tolerance" laws for drivers under 21 by 1998. The dispute over the use of "conditional" federal funding was evident in the 1998 congressional debate over the .08 BAL laws, when the battle lines were drawn between those who wanted to withhold federal highway monies from noncomplying states and those who wanted to offer an incentive for adoption rather than use a penalty.
In any value-laden field where research is highly susceptible to political bias, special efforts are required to preserve the integrity of the scientific process through peer review of proposals and publications and through the corrective effects of replication and reinterpretation of scientific findings. (The distortion of tobacco research is described by Bero and colleagues .) Research can never be value free, of course. Inevitably, a researcher's values influence the topics he or she chooses to investigate and the discussion of the possible implications of study findings. Yet every reasonable effort should be made to minimize the influence—and the appearance—of bias on the study methods and the analysis of results.
It is also important for investigators to avoid becoming so invested in a particular policy position that they compromise public confidence in the objectivity and integrity of the scientific process. Some investigators try to do this by eschewing advocacy altogether, and the committee believes that the injury field would benefit from a stronger cadre of "pure scientists" who try to maintain an objective stance on their work. However, it would go too far to insist that all injury scientists abstain from advocacy. As noted in Chapter 7, advocacy on behalf of injury prevention is a key component of public health practice, and injury scientists may properly want to assume the burdens—and risks—of advocacy. How to balance the demands of science and advocacy is one of the ongoing challenges for the field.
It is customary to summarize the knowledge, activities, and challenges of the injury field by categorizing injuries according to mechanism (motor vehicle, firearm, fall, fire, etc.), intentionality (unintentional, assaultive, and self-inflicted), or context (transportation, residential, recreational, and occupational). The committee decided not to use any of these customary devices to organize