The Sentencing Reform Act provides a determinate sentencing system in which sentencing courts generally impose sentences within a standard range.  The standard range for a person is determined by reference to a grid, which provides a base sentence according to the person's offender score and the seriousness level of the present offense.  The offender score is a point total based on an individual's prior juvenile dispositions and adult convictions.  Certain prior dispositions and convictions are excluded from offender score calculations if the person remains crime-free in the community for a specified period of time following release.

An individual's juvenile disposition records are included in offender score calculations if the person is convicted of a subsequent adult felony.  Prior juvenile dispositions are typically worth fewer points than equivalent adult convictions depending on the nature of the prior offense and the severity of the current offense.  Most crimes committed by persons under 18 years of age are adjudicated in juvenile court, but certain cases are transferred to adult court.  If a person under 18 years of age is convicted in adult court, the conviction is considered an adult conviction for subsequent offender score calculations.

A person's prior juvenile dispositions may not be included in the person's offender score calculations for any subsequent adult convictions, except for adjudications of guilt for Murder in the first degree, Murder in the second degree, and class A felony sex offenses.

Out-of-state or federal convictions that would have been presumptively adjudicated in juvenile court under Washington law may not be included in the offender score unless they are comparable to Murder in the first or second degree, or a class A felony sex offense.

When a person has multiple prior convictions for offenses committed before July 1, 1986, all adjudications served concurrently shall be counted as one offense for purposes of computing the offender score.