(II) When evaluating the criterion specified in subclause (I), the juvenile court may give weight to any relevant factor, including, but not limited to, the actual behavior of the person, the mental state of the person, the person's degree of involvement in the crime, the level of harm actually caused by the person, and the person's mental and emotional development.
A determination that the minor is a fit and proper subject to be dealt with under the juvenile court law shall be based on a finding of amenability after consideration of the criteria set forth in subclause (I) of clauses (i) to (v), inclusive, and findings therefore recited in the order as to each of those criteria that the minor is fit and proper under each and every one of those criteria. In making a finding of fitness, the court may consider extenuating and mitigating circumstances in evaluating each of those criteria. In any case in which the hearing has been noticed pursuant to this section, the court shall postpone the taking of a plea to the petition until the conclusion of the fitness hearing and no plea that may have been entered already shall constitute evidence at the hearing. If the minor is found to be a fit and proper subject to be dealt with under the juvenile court law pursuant to this subdivision, the minor shall be committed to placement in a juvenile hall, ranch camp, forestry camp, boot camp, or secure juvenile home pursuant to Section 730, or in any institution operated by the Department of Corrections and Rehabilitation, Division of Juvenile Facilities.