The study is the first since the 1960s to try to determine the percentage of youth who are arrested. Previously, the research estimated that 22% of Americans had been arrested at least once for a non-traffic violation by age 23.
“We say in the paper that we think the real figure is on the order of 1 in 3,” says Robert Brame, lead author of the new study and a professor of criminal justice and criminology at the University of North Carolina at Charlotte.
The broad range in the estimate found by Brame and his team — from 25.3% to 41.4% — is due to missing data. The researchers used 1997-2008 data from the National Survey of Youth, which included more than 7,000 teens, but some didn’t have data from some of the years.
Researchers have not completed an analysis of the data by race, but prior studies suggest that minorities are arrested more frequently than whites. Previous research finds, for example, that black youth are arrested at double the rate of white youth for drug crimes, even though a larger proportion of white youth actually use and sell drugs.
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Although it may seem shocking that at least one-third of U.S. youth has an arrest record, those who study juvenile crime don’t find the figure to be out of line. Since the 1970s, America has become much tougher on crime, lengthening sentences, increasing the police force and quintupling the number of people incarcerated. During that time, the number of Americans in prison has gone from half a million to 2.3 million, with approximately 93,000 incarcerated youth. Given the changes in the criminal justice system, some increase in youth arrests was to be expected.
“As a criminologist, I’m not terribly surprised by it,” says Brame.
The study captured arrests for all offenses other than traffic violations, including underage drinking, shoplifting, truancy, robbery, assault and murder. Most teens who are arrested are cited for minor infractions and don’t end up imprisoned. Still, for those who are, the detrimental effect of being detained may outlast the actual sentence.
Although the literature is mixed, several previous studies indicate that kids who are incarcerated do significantly worse later on, compared with those who are given alternative sentences that allow them to remain in their communities. One study, for example, compared children who committed the same crimes but wound up with harsh or lenient sentences: those who were sentenced to juvenile detention were three times more likely to be re-incarcerated as adults, compared with those whose judges gave them lighter, alternative sentences.
“It’s premature to say that we know sanctions for juvenile justice are ‘crimogenic,’” says Brame. “It may vary by type of offender, jurisdiction and types of services.”
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But researchers do know that teens who wind up in trouble with the law tend to have early risk factors, such as having a troubled family, childhood behavior problems or difficulty in school. About two-thirds of teens who serve time in a correctional institution have a serious mental illness. Given that these risk factors can arise early, Brame thinks that pediatricians may be able to make a difference.
If pediatricians are made aware of how common arrest is, Brame says, they can identify at-risk kids and their parents, and connect families with services that can help troubled youth find better ways to cope, helping to either prevent arrest or mitigate its consequences.
The study was published in Pediatrics.
Maia Szalavitz is a health writer at TIME.com. Find her on Twitter at @maiasz. You can also continue the discussion on TIME Healthland’s Facebook page and on Twitter at @TIMEHealthland.