WASHINGTON -- Every state allows children under 16 to be tried as adults, but new research indicates that many cannot understand their situations well enough to aid their defense.
The private MacArthur Foundation study released today says that many children under 16 had as much difficulty grasping the complex legal proceedings as adults who had been ruled incompetent to go to court.
''In all likelihood, a large number of juveniles who are being tried as adults are not competent to stand trial,'' said Laurence Steinberg, director of the MacArthur division that conducted the study and a professor of psychology at Temple University.
Kent Scheidegger, legal director of the conservative Criminal Justice Legal Foundation, said the vast majority of teenagers, even young ones, know enough to be tried in adult court. ''The notion that teenagers are not capable of understanding what is going on I find not credible in the case of mentally normal teenagers,'' he said.
The new study, by the John D. and Catherine T. MacArthur Foundation Research Network on Adolescent Development and Juvenile Justice, looked at more than 1,400 people between the ages of 11 and 24 in Philadelphia, Los Angeles, northern and eastern Virginia, and northern Florida.
Subjects were given intelligence tests and asked to respond to several hypothetical legal situations, such as whether to confess to a police officer. The results found that one-third of those 11 to 13 and one-fifth of those 14 or 15 could not understand the proceedings or help lawyers defend them. The study recommends that states reconsider the minimum age for juveniles to be tried as adults or to develop a system for evaluating young defendants' competence.
The report follows a decade of state efforts to make it easier to try children as adults. Between 1992 and 1999, every state but Nebraska passed such laws, according to the National Center for Juvenile Justice, a private, nonprofit research group.
Twenty-three states have no minimum age. Two, Kansas and Vermont, can try 10-year-old children as adults.
''Juvenile crime, juvenile violence was a hot story for many years,'' said Melissa Sickmund, a senior research associate with the juvenile justice group. ''Politicians responded by trying them as adults.''
About 25,000 children a year have their cases sent to adult courts instead of being tried in juvenile courts, whose convicted defendants are usually set free by the time they turn 21.
Some judges have rebelled against prosecuting youngsters as adults. Nathaniel Abraham of Michigan was 11 when he became the first child tried as an adult for first-degree murder. After the boy was convicted of second-degree murder, a county judge called the law ''fundamentally flawed'' and sentenced the boy to youth detention rather than life imprisonment.
In Texas, Lacresha Murray was twice convicted in the death of a 2-year-old who spent the day in her home. Murray was 11 years old when she admitted to police, after lengthy questioning without guardians or lawyers, that she might have dropped and kicked the toddler. A state judge dismissed all criminal charges against her.
California voters passed a measure in March 2000 to allow prosecutors to charge juveniles as adults without a judge's approval, which cheered Maggie Elvey, who heads the Sacramento office of Crime Victims United of California, an advocacy group.
''When it's a vicious, brutal crime, I don't want those guys living next to anybody's family again,'' said Elvey, whose husband was beaten to death almost 10 years ago by two boys, 15 and 16, using a metal pipe.
The Chicago-based MacArthur Foundation is a private, nonpartisan organization best known for its ''genius grants,'' the awards that allow scholars, scientists, artists, and others to pursue their work.