Arrests of teenagers in California plummeted by one-fifth last year.

A January state law that makes simple marijuana possession a misdemeanor, for the most part, is responsible for the 20 percent drop in 2011, says a recent analysis by the Center on Juvenile and Criminal Justice.

The policy briefing says that arrests of those under 18 in the Golden State are at …

… their lowest level since statewide statistics were first compiled in 1954.

The paper notes that felony arrests were down 17 percent, misdemeanors decreased by 21 percent, and even homicide dipped by 26 percent compared to 2010.

Here's the money 'graf:

Credit: Dank Depot / Flickr

Credit: Dank Depot / Flickr

The trend was led by a 47% decrease in drug offense arrests from 2010. The largest contributor to this decrease was a drop of 9,000 in youths' low-level marijuana possession arrests under a new state law reducing that offense from a misdemeanor to an infraction …

Authors note that “on January 1, 2011, SB 1449 reduced most simple marijuana possessions to an infraction involving a mere citation rather than criminal arrest.”

That's essentially decriminalization.

The Center says in the 1950s youths were responsible for nearly 9 percent of arrests statewide; today they're good for 3.4 percent.

(At the same time there has been some evidence that older adults these days, products of the 1960s and '70s, are actually having worse problems with criminal behavior because of drug addiction).

Researchers conclude:

The only two factors definitively associated with (or, at least, positively accompanying) the dramatic decline in youth arrests are the relaxing of marijuana possession laws and the improvement in economic well-being among young people in the state's poorest neighborhoods.

[@dennisjromero / djromero@laweekly.com / @LAWeeklyNews]

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