Even as that trend is being reversed, all states retain the ability to prosecute especially violent youths as adults, in some cases with no minimum age limit. But those cases make up a tiny portion of the total juvenile caseload nationwide. In 2007, there were fewer than 9,000 juvenile cases waived to adult court, out of nearly one million juvenile prosecutions, according to the most recent national estimate from the Justice Department.

In New York, where 45,873 youths ages 16 and 17 were arrested last year, proponents of raising the age of adult criminal responsibility have attempted to push the issue in the past two months. Aides to Gov. Andrew M. Cuomo did not immediately respond to questions about his position on the issue.

In January, an advisory board to the Governor’s Children’s Cabinet, a group of state officials with oversight over youth issues, released a report calling for a task force to examine raising the age.

Around that time, members of the New York State Bar Association children’s committee drafted legislation to establish such a task force, and they are looking for support from legislators and the governor’s office. Michael A. Corriero, a retired judge who presided over Manhattan’s special court for 13-, 14- and 15-year-old offenders who were tried as adults, testified at a City Council committee hearing in January that the current system was ineffective.

Any efforts to raise the age would contend with questions about whether the state’s juvenile justice system, already under strain, can handle an even bigger load. Four youth prisons were placed under federal oversight last year because of complaints of physical abuse of inmates and a lack of mental health counseling. Mayor Michael R. Bloomberg has proposed that the city be allowed to handle its own juvenile cases.

In interviews, New York City judges asserted that the juvenile court system as it was currently financed would be overwhelmed by adding 16- and 17-year-old offenders. “We would need a big infusion of funding and staff to make it happen with that age group,” said Fran Lubow, a judge in Queens Family Court. “I don’t see that happening in our current budget circumstances.”

Some judges said teenagers in adult court were well served with a host of special rehabilitation programs, and noted that young defendants in adult court automatically had their first misdemeanor conviction sealed, and that judges had the discretion to seal later convictions.