Patricia Zapf provides this helpful this helpful summary.
The authors note that “the nature of adolescent risk perception may not only increase the chances of criminal behavior, it may interfere with the deterrent intent of legal sanctions. If, as suggested by the developmental literature, adolescents tend to discount risks and future consequences, the are unlikely to give sufficient weight to the potential legal consequences of law-breaking prior to indulging in it. Rather, they will be more swayed by the potential short-term rewards of the illegal action (e.g., thrill, novelty, revenge, enhanced social status)” (p. 421).
“To summarize, developmental immaturity, insofar as it contributes to criminal behavior, diminishes adolescent culpability, reduces the benefit-to-cost ratio of incarcerating juvenile offenders, and impedes the deterrent effect of punitive responses” (p. 421).