Why does the problem of sentencing disparity exist?
There are two main reasons for sentencing disparities.
First, there is the fact that judges are often given discretion in imposing sentences. This can seem like the logical thing to do. It makes sense that not every offender should be treated like every other offender. People who commit the same crime can have very different backgrounds and can seem to deserve very different punishments. We would not want a system in which judges are locked into certain sentences regardless of the circumstances of an individual case. Therefore, we give judges some discretion. However, this makes it possible for disparities to exist in sentencing.
Second, there is the fact that judges are human beings who have different attitudes and who have personal opinions. Different judges may give different sentences simply because they have different personal philosophies about crime. In addition, the same judge might treat different offenders differently because of their own personal prejudices. A judge might be more lenient to women because he feels it is chivalrous to do so. Another might be more lenient to offenders who go to church because he thinks that they are more likely to be good people at heart.
Simply put, we want our justice system to be somewhat flexible. Because of this, we are likely always to have disparity in sentencing.