ALEXANDRIA, Va. — With every new tragedy involving children accused of murder, there is a louder drumbeat of demands for harsher laws to deal with what some experts say is a new breed of killer. So it was again in August when two Chicago boys, ages 7 and 8, were charged with the murder of an 11-year-old girl, and two Arkansas boys were sentenced for the shooting deaths of four classmates and a teacher.

Many politicians and others have called for allowing children under the age of 10 to be tried in adult courts andto be sentenced to adult prisons. The Texas Legislature has even debated imposing the death penalty on children as young as 11 years old, although the actual execution would be postponed until he or she turned 17.

But as the former commissioner of youth corrections in Massachusetts and Pennsylvania, I know from experience that punishing children with harsher sentences and conditions is not the solution.

First, there has not been a surge in child killers. Children under the age of 18 have been responsible for fewer than one-twentieth of the murders committed in this country for the last two decades at least. (Approximately 10 percent of these crimes involve young people who have killed their parents, often within the context of abusive relationships.)

After reviewing 975 homicides in Cuyahoga County, Ohio, over 42 months in the early 1970’s, for example, the Cleveland deputy coroner found five homicides committed by children 8 years of age and younger — some of them unusually brutal. According to the Justice Policy Institute, which analyzed F.B.I. statistics, nationally there were 25 recorded homicides committed by children under the age of 13 in 1965, versus 16 in 1996. And despite the rash of school shootings in recent months, fewer incidents occurred this year than in some past years. For example, school shootings caused 55 deaths in 1992-93, in contrast with 40 in 1997-98.

This is not to deny that juvenile violence is an important problem. But consider what effects harsher penalties for young people had in the past. In Massachusetts and Pennsylvania, for example, children were brutally treated in both adult and juvenile correctional institutions a generation ago. Boys as young as 14 were often sentenced to three to five years for offenses as minor as vandalism and small burglaries. Beatings and long stretches in solitary confinement were common.

In the early and mid-1970’s, I helped several states deinstitutionalize their juvenile justice systems. In Massachusetts, Gov. Frank Sargent, a Republican, replaced all the reform schools with some 200 different nonprofit programs, including group homes and individual intensive treatment for the worst cases. In some instances, we had one worker supervising no more than one or two youngsters. Institutionalization is so expensive — it currently costs $50,000 to $70,000 a year per child in most states — that these options did not cost the state more money.

More important, making the juvenile justice system less strict had positive results. Independent studies found that a decade after Massachusetts closed its reform schools, the recidivism rate was much lower than in states that continued to rely on reform schools and prisons. In Massachusetts, 24 percent of juveniles who had been released for 36 months were reincarcerated or recommitted. In contrast, Texas had a recidivism rate of 43 percent, and California’s rate was 62 percent. And when Massachusetts juveniles committed new crimes, the violations were less serious than those by offenders in states with stricter laws.

Perhaps our reforms were successful because they spoke to civility and decency. Many people would argue that today’s young criminals deserve nothing of the kind. But they should know that harsher penalties will do nothing to protect society.