. >> matthew cade was the head of the california department of corrections. >> so if a crime is reported, then we go back to the tracks and see if we can place them at the scene of the crime. >> gardner a lower-risk offender? again says matthew cade, it was the assessment method itself, its limitations, that failed to spot gardner's potential to be dangerous. but when gardner was paroled -- >> this was the most accurate tool in the world, and so we used it. i wish we'd known then what we know now, but the department just didn't have anything else to use at the time. >> it was based on factors such as age, number of offenses, type of crime. >> i think the public wants us to be able to predict who exactly is going to do what. we'll never be able to do that. low risk doesn't mean no risk. >> improvements have been made. there's required gps tracking of all sex offender parolees and treatment for those parolees. the treatment includes the use of polygraph tests in an effort to keep track of parolees to see if they're in danger of re-offending. >> we'll move then to the victim impact statemen