Those arrests are for everything from underage drinking and petty theft to violent crime, researchers said. They added that the increase might not necessarily reflect more criminal behavior in youth, but rather a police force that's more apt to arrest young people than in the past.

"The vast majority of these kids will never be arrested again," said John Paul Wright, who studies juvenile delinquency at the University of Cincinnati's Institute of Crime Science, but wasn't involved in the new study.

"The real serious ones are embedded in the bigger population of kids who are just picking up one arrest," he told Reuters Health.

Though violent crimes might be on the rarer end of the spectrum of offenses, the study's lead author pointed to the importance of catching the early warning signs of criminal behavior in adolescents and young adults, saying that pediatricians and parents can both play a role in turning those youngsters around.

Robert Brame of the University of North Carolina at Charlotte and his colleagues analyzed data from a nationally-representative youth survey conducted between 1997 and 2008.

A group of more than 7,000 adolescents age 12 to 16 in the study's first year filled out the annual surveys with questions including if and when they had ever been arrested.

At age 12, less than one percent of participants who responded had been arrested. By the time they were 23, that climbed to 30 percent with a history of arrest.

That compares to an estimated 22 percent of young adults who had been arrested in 1965, from a past study.

"It was certainly higher than we expected based on what we saw in the 1960s, but it wasn't dramatically higher," said Brame.

Arrests in adolescents are especially worrisome, he told Reuters Health, because many repeat offenders start their "criminal career" at a young age.

The researchers said it seems that the criminal justice system has taken to arresting both the young and old more than it did in the past, when fines and citations might have been given to some people who are now arrested.

"If (police) find kids that are intoxicated or they have pulled over someone intoxicated... now, nine times out of 10 they're going to make an arrest," Wright told Reuters Health.

"We do have to question if arrest is an appropriate intervention in all circumstances, or if we need to rethink some of the policies we have enacted."

He pointed out that young people who have an arrest on their record might have more trouble getting jobs in the future. It's one thing if that's because they were involved in a violent crime, he continued, but another if their offence was non-violent, like drinking underage or smoking marijuana.

"Arrest does have major social implications for people as they transition from adolescence to adulthood," Wright said.

While the report didn't ask youth why they had been arrested, Brame said that common offenses in that age group also include stealing, vandalizing and arson.

For most minor offenses, teens and young adults will get a term of probation or another minor penalty, he said. The most serious adolescent offenders and those with a prior record could be prosecuted as adults and end up getting a prison sentence.

Brame said that being poor, struggling in school and having a difficult home life have all been linked to a higher risk of arrest in that age group.

He and his colleagues wrote in Pediatrics on Monday that other warning signs of delinquent behavior include early instances of aggression and bullying, hyperactivity and delayed development.

Pediatricians might be able to recognize those warning signs more clearly than parents, and can point kids toward resources to help keep them out of trouble, such as counseling services, Brame said.

"We urge that parents who are concerned about their kids' well-being, that they get those kids in to see a pediatrician on a regular basis so the pediatrician can do the things they're trained to do."

SOURCE: bit.ly/jsoh2P Pediatrics, online December 19, 2011.

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