Decades of research have shown that the criminal courts sentence black defendants more harshly than whites. But a striking new investigation of sentencing disparities in Florida by The Sarasota Herald-Tribune expands our understanding of this problem in two important ways.

It exposes the fact that African-American defendants get more time behind bars — sometimes twice the prison terms of whites with identical criminal histories — when they commit the same crimes under identical circumstances. It also shows how bias on the part of individual judges and prosecutors drives sentencing inequity.

The Florida Legislature has been wrestling with this issue for decades. In the 1980s, for example, it tried to change sentencing policies that varied widely from place to place by creating sentencing guidelines. Today, prosecutors assign defendants points — based on the seriousness of their crime, the circumstances of their arrest and whether or not they have prior convictions — to determine the minimum sentence required by law.