Laws that send teen offenders to the adult justice system "do more harm than good" in reducing violent or other criminal behavior, according to a task force report reviewing studies conducted over two decades.
The group of public health experts, appointed by the federal Centers for Disease Control, said "transfer policies have generally resulted in increased arrests for subsequent crimes, including violent crime" among teens sent to the adult system, compared to those who remain in juvenile court.
The panel -- known as the Task Force on Community Preventive Services -- recommended against tougher transfer laws in a report published last week. The CDC evaluated nine studies for the group.
But the report also noted that the research didn't include the least or most violent cases, and that it was possible that transferring very serious offenders to adult court might be effective.
One study mentioned compared juvenile offenders in New York -- where anyone 16 or older is considered an adult, and even younger for violent crimes -- with kids in New Jersey, where the age cutoff is 18 and few teens are waived to the adult court.
The two groups of kids were studied over seven years during the 1980s and 1990s and those who were prosecuted as adults were 28 percent more likely to commit violent crimes, according to Jeffrey Fagan, a professor of law and public health at Columbia University. The research he led was conducted in separate decades with separate examples and the reached the same conclusion.
Fagan said the two groups were matched on several counts -- including age and prior crimes and incarceration -- and the higher rate was consistent, even when the New York kids didn't end up in prison.
A 1996 Florida study done by Donna Bishop, now a professor at Northeastern University in Boston, and others found that juveniles transferred to adult court were more likely to commit more crimes, faster and at a higher rate than those who stayed in the juvenile system. The offenses were more serious. The kids were followed over six years.
Bishop also looked at a second group of kids during 1998-99 and found similar results.
Some experts argue these studies are flawed, that the two groups aren't equally matched -- odds are the kids tried as adults were more serious offenders even if they committed the same type of crime.
Howard Snyder, director of systems research at the National Center for Juvenile Justice, says some of these studies are "comparing apples to oranges. They went too far in concluding the adult system is bad. We don't have enough research to say that."
Two other studies released in 2006 (not among those reviewed by the CDC) discounted state laws passed between 1975 and 2003 making it easier to treat juvenile offenders as adults or giving prosecutors more discretion to do so. Generally, the studies said, they didn't deter kids from committing crimes.
"Kids really don't appreciate the long-term consequences of their actions," says Benjamin Steiner, a research associate at the University of Cincinnati who led the studies.