That's different, though. The goal of a parole suitability hearing is to determine whether an inmate poses an unreasonable risk of danger to society if released from prison. A data point like "this prisoner murdered some people" is very relevant to that determination.
OJ's parole was fair, and done by the book. OJ's sentencing for the armed robbery (30 years - his friends who brought the guns, and had a number of prior felonies all got probation) unfairly reflected his murder trial. The judge and jury were almost certainly out to get him.
