Both adults and youth. It's kind of revealing to look at the headline right below this one,
"Police in the US Kill Citizens at Over 70 Times the Rate of Other First-World Nations"

Perhaps the notoriously high-IQ police have been doing all the thinking.

They wouldn't be there!

WILLIAMS v. ILLINOIS, 399 U.S. 235 (1970)
399 U.S. 235
WILLIAMS v. ILLINOIS
APPEAL FROM THE SUPREME COURT OF ILLINOIS
No. 1089.
Argued April 22, 1970
Decided June 29, 1970

Appellant was given the maximum sentence for petty theft under Illinois law of one year's imprisonment and a $500 fine, plus $5 in court costs. The judgment, as permitted by statute, provided that if when the one-year sentence expired he did not pay the monetary obligations, he had to remain in jail to work them off at the rate of $5 a day. While in jail appellant, alleging indigency, unsuccessfully petitioned the sentencing judge to vacate that portion of the order confining him to jail after the sentence expired, because of nonpayment of the fine and costs. The Illinois Supreme Court rejected appellant's claim that the state statutory provision constituted discriminatory treatment against those unable to pay a fine and court costs, and affirmed the lower court's dismissal of appellant's petition, holding that "there is no denial of equal protection of the law when an indigent defendant is imprisoned to satisfy payment of the fine." Held: Though a State has considerable latitude in fixing the punishment for state crimes and may impose alternative sanctions, it may not under the Equal Protection Clause subject a certain class of convicted defendants to a period of imprisonment beyond the statutory maximum solely by reason of their indigency. Pp. 239-245.

http://caselaw.lp.findlaw.com/scripts/getcase.pl?court=US&vol=399&invol=235

I worked as secretary to counsel for Mr. Williams. My boss, Stanley A. Bass, was counsel at a legal services office in the Cook County Jail, and he took cases in support of prisoners' rights, to Illinois and U.S. courts, including the Supreme Court. We won this one.

Outstanding! Thank you for posting that link.

My boss was, and probably still is, one of the best attorneys in the country, and I was SOOOO fortunate to have found him (and my first job, after college, as a secretary at the Civil Legal Services program at the Cook County Jail!!!) My father had always wanted me to attend law school, but until I met Stanley Bass (and other attorneys in Chicago,) I hadn't developed the interest. Couldn't avoid it, after this experience.

I was somewhat shocked, in a good way, to read our government reps are having
these conversations and I had no idea of Kennedy's position on incarceration and
mandatory sentencing.

Long way to go, yet they are talking.

The Supremes, individually, tend to develop interests and concerns about many aspects of the U.S. legal system, and voice those concerns, often to everyones' benefit.