The Sentencing Reform Act, passed by Congress in 1984, established the federal sentencing guidelines. The guidelines were designed to improve standardization in punishments handed out to convicted criminals by limiting what had been federal judges' nearly unfettered discretion in sentencing (Anderson, Kling, and Stith 1999; Stith and Cabranes 1998). For federal crimes committed after November 1, 1987, the Act established that sentences of incarceration were to be determined by a table mapping the severity of the offense (a level between 1 and 43) and the defendant's criminal history (a level between I and VI) to a potential range of months imprisonment. Table 1 shows the United States Sentencing Commission's (USSC) Sentencing Table. A defendant, for example, with a "final offense level" of 20 and a "criminal history category" of IH should, according to the guidelines, be sentenced to somewhere between 41 and 51 months in federal prison. (The actual sentence would be an integer within that range). (1) The Act also abolished parole for federal crimes, though up to 15% of an inmate's sentence could be reduced for good behavior. (2)
The Sentencing Reform Act declared that Table 1's guideline ranges were "mandatory"--federal judges had to incur a nontrivial cost to sentence a defendant outside them. But on January 12, 2005, the United States Supreme Court ruled in the two-part decision U.S. vs. Booker that (a)the sentencing guidelines violated a defendant's constitutional fight to a jury trial; (3) and (b) in order to maintain constitutionality, the guidelines were to be "effectively advisory" instead of mandatory. (4) Legal observers had expected the overturning of the federal sentencing guidelines system since June 2004, when the Supreme Court decision Blakely v. Washington invalidated Washington state's sentencing guidelines system because it violated a defendant's right to a jury trial (Denniston 2004).
By making the sentencing guidelines advisory rather than mandatory, Booker reduced the cost of sentencing outside the guidelines and increased the ambiguity of federal judges' sentencing decisions. According to Bertrand, Chugh, and Mullainathan (2005), "ambiguity" is one of three situations in which implicit discrimination is likely to occur. (The other two situations are "inattentiveness to task" and "time pressure.") Implicit discrimination, unlike taste-based discrimination (Becker 1957) or statistical discrimination (Aigner and Cain 1977), reflects implicit attitudes that Bertrand, Chugh, and Mullainathan (2005) state are "unintentional and outside of the discriminator's awareness." Research indicating implicit discrimination include findings that National Basketball Association referees call fewer fouls against players of their own race (Price and Wolfers 2010), that Major League Baseball umpires are more likely to call strikes when the pitcher is of their own race (Parsons et al. 2007), and that screeners of resumes are more likely to ignore job applications with "black" names than ones with "white" names (Bertrand and Mullainathan 2004). Each of these scenarios describes a situation where ambiguity, inattentiveness, or time pressure is a factor, and where a statistically significant amount of discriminatory treatment is detected. (5)
This paper tests whether the Booker decision, by increasing the ambiguity of federal judges' sentencing decisions, increased manifestations of discrimination in accordance with the hypothesis of Bertrand, Chugh, and Mullainathan (2005). Difference-in-difference results show that conditional on a defendant's Table 1 guideline cell, Booker reduced sentences significantly for the default group of defendants--white, male, U.S. citizens who never earned a high school diploma. Female defendants and defendants with terminal high school degrees received significantly larger Booker-related sentence reductions and college graduates received significantly smaller ones. …