Federal actions to incentivise state adoption of 0.08†g/dL blood alcohol concentration laws.

OBJECTIVE: To model rates of 0.08 g/dL blood alcohol concentration (BAC) per se law implementation among the states associated with (1) a federal incentive grant programme and (2) a threat from the federal government to withhold highway transportation funds. METHODS: An observational study of state-level 0.08 g/dL BAC per se law enactment among all 50 US states from 1982 to 2006 using a parametric survival analysis to assess the time-dependent risk of policy enactment. RESULTS: The federal government's threat to withhold transportation funds was associated with a 10.30 times greater hazard (HR: 10.30, 95% CI 3.88 to 27.36) of states adopting a 0.08 g/dL BAC law compared with periods of time when this threat was not in place. The incentive grant programme created by the federal government was associated with a non-significant 17% decrease in the hazard of states adopting a 0.08 g/dL BAC law (HR: 0.83, 95% CI 0.35 to 2.0). CONCLUSION: In the case of 0.08 g/dL BAC per se laws, the federal government's threat to withhold transportation funds was effective at accelerating policy adoption.