Attorney General Eric Holder on Friday expressed concern about the fairness of judges who rely on big data to sentence criminal defendants, saying the use of such “risk assessments” in several states could exacerbate racial disparities among the prison population.

Holder, who made the comments during a Philadelphia speech to criminal defense lawyers, said the use of such data results in unfair treatment of minorities.

“Basing a sentence on something other than the conduct of the person involved and the person’s record, you’re looking, for instance, at factors like the person’s education level, what neighborhood the person comes from,” Holder said in an interview with PBS on Thursday. “They’re using this as a predictor of how likely this person as an individual is going to be a recidivist. I’m not at all certain that I’m comfortable with that … I think the result is fundamental unfairness.”

Research has shown that racial minorities who don’t have regular jobs or steady families are likely to be charged with more severe crimes, leading to longer prison sentences, according to Nazgol Ghandnooh, a research analyst for the Sentencing Project, an organization dedicated to sentencing reform in U.S. prisons.

“A lot of the criteria to measure risk has to do with disparities in race and class to the extent that we’re looking at data factors like employment or level of education or marital status and family resources … things someone is not able to change,” Ghandnooh said. “We are creating a two-tiered system of sentencing.”

Though Holder maintained that a person’s record could be useful in sentencing, Ghandnooh disagreed.

“Some proponents describe past records as a measure of risk, but what we know is that a person’s past record is the product of two things: One is engagement in crime and the other is the level of surveillance they experience,” Ghandnooh said, adding that police forces typically have a heavier presence in low-income and minority areas — making individuals in those communities more likely to be arrested in the first place.

“I think Holder’s statement is helpful because it brings attention to the fact that just focusing on addressing the really high levels of incarceration we have in this country is not sufficient to address its racial disparities,” she said.

The attorney general’s Thursday speech marked one year since his “Smart on Crime” initiative, in which Holder instructed federal prosecutors to end mandatory minimum sentences for many nonviolent drug defendants.

In April, the Justice Department launched a new clemency push to commute mandatory minimum sentences for nonviolent drug offenders. The changes are expected to rein in runaway federal prison costs and create a fairer criminal justice system.

In the wake of that decision, more than 3,300 federal inmates have applied to have their sentences cut short, nearly five times the number who applied for commutations in the same period the year before, according to data obtained by The Associated Press.

Nonviolent drug offenders, the target population of Holder’s reforms, represent nearly half the estimated 216,000 inmates in federal prisons. The clemency reforms are part of an effort to reduce prison costs and alleviate what Holder has called inequities in the criminal justice system.

“These older, stringent punishments that are out of line with sentences imposed under today’s laws erode people’s confidence in our criminal justice system,” Deputy Attorney General James Cole said in announcing the new criteria in April.

With wire services