Association for Public Policy Analysis & Management

Introduction: Mandatory minimum sentences have been used in the United States to target crimes seen as especially serious or disruptive for centuries. However, the efficacy of these laws in reducing the undesirable behaviors remains unclear.  The Anti-Drug Abuse Act of 1986 (ADAA), with amendments in 1988, set mandatory minimum prison sentences for drug charges. Under this law, 5g of crack cocaine was equivalent to 500g of powder cocaine for sentencing purposes. This 100:1 ratio was reduced to 18:1 under the Fair Sentencing Act of 2010 (FSA). This study assessed the impact of mandatory minimum sentences on crack and powder cocaine use under the differential sentencing initiated by ADAA and then reduced by FSA. The study hypothesized that if mandatory minimums reduce drug use behavior, both crack and powder cocaine use should decrease after implementation of the ADAA, with crack cocaine use decreasing by a larger percent than powder cocaine.  After FSA, powder cocaine use should remain unchanged while crack cocaine use increased.

Methods: Data come from the National Survey on Drug Use and Health (NSDUH). The 1985 & 1990 waves (N=6,518) were used to examine the impact of the ADAA; the 2009 & 2011 waves were used to examine the impact of the FSA (N=43,961). Weighted multivariable logistic regression was used to estimate the proportional change in past-year use of crack cocaine and powder cocaine before and after implementation of each law. Change is drug use rates were also compared against a negative control of prescription drugs, which were not included in either the ADAA or FSA.  Z-tests were used to test for equality of coefficients across the estimates.

Results: While crack cocaine use did not decline after the ADAA (odds ratio (OR): 0.72, p=0.09), both powder cocaine and prescription drug abuse decreased (respectively OR: 0.64, p<0.01; 0.59, p<0.01).  However, comparatively, the change in use rates did not differ by type of cocaine (Z-score: 0.51, p=0.70) or when compared against prescription drugs (crack v. prescription Z-score: -0.80, p=0.21; powder cocaine v prescriptions Z-score: -0.41, p=0.34). Use of all three drugs decreased after the FSA (Crack OR: 0.55, p<0.01; powder cocaine OR: 0.81, p<0.01; prescription drugs OR: 0.83, p<0.01), with crack cocaine decreasing more than prescription drug use (Z-score: 2.13, p=0.03). The difference between the decline in crack and powder cocaine after the FSA was not appreciable (Z-score: 1.89, p=0.06).

Conclusion: Despite differential penalties for crack and powder cocaine use under the ADAA, there was no differential impact on use by type of cocaine or in comparison to a negative control. Similarly, the reduction in penalties under the FSA did not differentially impact use: both forms of cocaine decreased over this period, as did use of drugs not included in the law. Therefore, it cannot be concluded that reduction in use was a direct result of these mandatory minimum policies. Policy makers aiming to discourage drug use behaviors should consider policies other than mandatory minimums to most effectively impact behaviors.