A new study from University of Sheffield researchers sheds light on the racial bias in U.S. court sentencing decisions by revealing that petty criminals who are African American face an increased likelihood of being jailed compared to their white counterparts, as well as longer sentences for low severity crimes.

Todd Hartman and his team analyzed over 17,000 criminal sentencing decisions from South Carolina in order to explore if, when and how race affects this process.

The study tested the "liberation hypothesis," which focuses on the flexibility of judges when sentencing, with a particular focus on relevant case facts. This hypothesis states that when case facts are unambiguous, including serious crimes and repeat offenders, they have little choice in their choice of punishment. Conversely, in more ambiguous cases, they are "liberated" from the constraints of the system and have the ability to exercise their own judgment more freely.

In order to test this hypothesis, the team chose study data from South Carolina due to the state's lack of sentencing guidelines, giving decision-makers the maximum amount of flexibility in their sentencing decisions. The results showed that the "black penalty" varied, depending on the criminal history of the offender.

With regards to offenders with low levels of criminal history, African Americans were more likely to be jailed than white people. Furthermore, the likelihood of their incarceration increased by as much as 43 percent for those with no criminal history, whereas those with a moderate criminal history only faced a 10 percent likelihood. However, when offenders had long criminal records, the impact of race was effectively neutralized.

Interestingly, African American offenders that committed low severity crimes received sentences that were longer than white offenders, but those that committed high severity crimes received shorter sentences on average than white offenders.

"Much of the recent media focus in the U.S. has been on racial disparities in law enforcement, most notably with coverage of police shootings, excessive force, and unlawful deaths," Hartman said in a press release. "Of course, this is just part of the story, as contact with law enforcement is only the first stage of the criminal justice system."

"Whether intentional or not, the fact that race appears to influence incarceration and criminal sentencing decisions is troubling," he added. "It is particularly concerning that this pattern of disparity appears to be affecting African American offenders with limited criminal histories or for less severe crimes."

The findings were published in the Feb. 29 issue of the Journal of Quantitative Criminology.