The ruling, which few people in the criminal justice system had expected, immediately called into question the use of prior juvenile offenses.
The two younger boys were charged with juvenile offenses.
This system seeks to address the root causes of juvenile offenses and to reduce recidivism.
The laws against juvenile offenses are still enforced.
The 11- and 12-year-old boys were charged with juvenile offenses.
Between 60-80% percent of adolescents, and pre-adolescents engage in some form of juvenile offense.
"Not one of them had anything on his record more serious than a juvenile offense or a speeding ticket," she said.
Cases involving weapons violations by juveniles grew by 86 percent between 1988 and 1992, more than any other juvenile offense.
Overall juvenile criminal offenses have declined in the last five years.
Most states seal at least some records of juvenile offenses.