Dr. Miller, shown here in 1995, was a nationally known advocate for the overhaul of juvenile justice. (Frank Johnston/The Washington Post)

When Jerome G. Miller arrived in Massachusetts in 1969 to lead an overhaul of the state’s reformatories for juvenile delinquents, young people incarcerated in the facilities, also known as training schools, were routinely gagged and bound.

In other cases, they were stripped of their clothing and placed in cells. There were reports that the youths drank from toilets and that corrections officers ordered them to kneel on pencils or strapped them to beds and beat the soles of their feet. One young man hanged himself.

“Training schools are so bad that the average kid would be better on the street,” Dr. Miller told Time magazine in 1972.

Dr. Miller, a psychiatric social worker who had once considered joining the Catholic priesthood, set out in his position as commissioner of Massachusetts’s youth services department to fix the reformatories. But he found their conditions so dire, and resistance to change so fierce, that he concluded a more radical move was necessary.

In 1972, in a controversial action that would bring sweeping changes to juvenile corrections across the United States, Dr. Miller began shutting down Massachusetts’s reformatories. He moved approximately 1,000 young people to foster care, group homes and other community-based accommodations in a project that became known as the “Massachusetts experiment” — and that today is widely considered a model for the treatment and rehabilitation of young offenders.

Dr. Miller, 83, died Aug. 7 at a nursing home in Woodstock, Va. The cause was complications from a series of strokes, said Herb Hoelter, a co-founder with Dr. Miller of the National Center on Institutions and Alternatives, a Baltimore-based provider of social and criminal justice services.

Dr. Miller once told The Washington Post that he amassed “an awful lot of enemies around the country” in his career as a criminologist, government administrator and writer. During his tenure in Massachusetts, in similar jobs in other states and as the court-appointed receiver of the District of Columbia’s child welfare system in the mid-1990s, he was criticized at times for being overly aggressive and insufficiently diplomatic in his efforts to upend long-standing institutions.

He clashed with many politicians and law enforcement leaders, with some opponents arguing that his leniency with troubled youths endangered public safety, and he acknowledged that management skills were not his strength. But he became broadly recognized for envisioning — and then demonstrating — a better way of handling delinquents before they turn to a life of crime.

“I would rate Jerry Miller the most influential juvenile justice and criminal justice reformer of the past 50 years,” Barry Krisberg, a criminologist at the University of California at Berkeley, said in an interview. “His approach to juvenile justice is today the national norm.”

Dr. Miller came to Massachusetts at a pivotal time in youth corrections. Two years earlier, in the landmark case In re Gault, the U.S. Supreme Court had affirmed that minors charged with crimes in juvenile courts were entitled, like adults, to due process protections.

“Under our Constitution,” wrote Justice Abe Fortas, “the condition of being a boy does not justify a kangaroo court.”

Massachusetts Gov. Francis W. Sargent, a Republican, hired Dr. Miller, then teaching at Ohio State University, amid growing outrage about the conditions of juvenile penal facilities. Beyond their cruelty, the institutions seemed ineffective. Recidivism reached 60 to 80 percent, according to a 1972 report in the New York Times.

And the cost — $10,000 per person per year in 1972 — was crushing. That figure, Dr. Miller told the Times, was “enough to send a child to Harvard with a $100-a-week allowance, a summer vacation in Europe, and once-a-week psychotherapy.”

In his early attempts to improve the reformatories, Dr. Miller instituted new rules, including one requiring any authority who placed a youngster in isolation to remain with him or her until the confinement ended. “The rule effectively stopped use of isolation,” Dr. Miller later recalled in a book about the experiment, “Last One Over the Wall” (1991).

Dr. Miller wrote that he was opposed by many correctional staff members, including some who seemed to let their charges run away — so that his methods might appear ineffective. Such resistance helped him conclude that the institutions could not be repaired and that they should instead be eliminated.

He relied in part on procedural tactics to gradually move the youths into new environments. His work in Massachusetts was “a human passage,” he wrote, “raucous, fitful, threatening, exhilarating, at times impulsive, often unpredictable, changing direction as we took advantage of unexpected opportunities — and always difficult. We lived for a time on the edge of bureaucracy, professional ethics, legality and politics.”

In time, studies by institutions including Harvard University and the National Council on Crime and Delinquency vindicated the Massachusetts experiment. It had not led to a spike in crime, as had been feared. The Boston Globe wrote that he had “left a legacy of humanity and hope where there had been regimentation and cruelty.”

In 1973, Dr. Miller became head of the Illinois Department of Children and Family Services, under Gov. Dan Walker (D). He later went to Pennsylvania as commissioner of children and youth under Gov. Milton J. Shapp (D). Dr. Miller closed a facility that he called a “human sewer” but was removed from daily authority when his plans for alternatives proved unpopular.

With Hoelter, Dr. Miller founded the National Center on Institutions and Alternatives in 1977. He was an outspoken critic of what he saw as race- and class-based inequality in criminal justice.

In 1995, he took over the District’s child welfare program, which include the troubled foster care system. He challenged traditional models of social work by advocating a more decentralized system, in which nonprofit organizations and community groups helped serve needy children, but resigned in 1997 in a bitter dispute with other officials.

Jerome Gilbert Miller was born in Wahpeton, N.D., on Dec. 8, 1931. He received a bachelor’s degree in philosophy at Maryknoll College, a now closed Catholic seminary in Glen Ellyn, Ill., in 1954 and, three years later, a master’s degree in social work from Loyola University Chicago.

He spent more than a decade in the Air Force, serving as a psychiatric social worker, and received a doctorate in social work from Catholic University in 1965.

Besides his books about the Massachusetts reformatories, Dr. Miller wrote “Search and Destroy: African-American Males in the Criminal Justice System” (1996).

Survivors include his wife of 47 years, the former Charlene Coleman, of Woodstock. The Millers acted as guardians to two children over the years.

In his book about the Massachusetts experiment, Dr. Miller wrote that “acknowledging an evil act and knowing the capacity for evil in a human being” is different from “labeling a person evil.”

“That is much too simple and is the most naive of conclusions,” he wrote. “It is an unforgivable sin which by its nature closes the door on redemption. My purpose has not been to excise human responsibility, overlook the demands of justice, or deny personal accountability. I have tried to nurture hope.”