NARRATION: Along this stretch of grassy road, one night in early September, 1994, when most grade schoolers were getting ready for a new school year, a grisly murder took place.

ARCHIVAL (ABC, 2-21-95):PETER JENNINGS: In Chicago, the body of an 11-year-old gang member nicknamed Yummy is found beneath an underpass.

ARCHIVAL (CBS, 9-15-94):VICKI MABREY: Police say Robert was murdered by two members of his own gang 16-year-old Craig Hardaway and his younger brother.

NARRATION: Derrick Hardaway was 14 when he and his brother drove to the underpass to kill Robert Sandifer, or Yummy. Sandifer himself had shot and killed a teenage girl before he was murdered. Derrick waited in the car while Craig pulled the trigger.

DERRICK HARDAWAY: I remember the night when things took place. He got a page from a guy named Kenny. Im not actually sure what he said to my brother, but it was to kill Robert.

NARRATION: Derrick and his older brother belonged to Chicagos Black Disciples gang.

DERRICK HARDAWAY: If I was told to do certain things, even if I didnt want to do it, it was either do what Im being told or have it done to me.

NARRATION: Robert Sandifers murder was big news. The story scared people says criminologist Barry Krisberg.

BARRY KRISBERG (FORMER CRIMINOLOGIST, UNIVERSITY OF CALIFORNIA, BERKELEY): This was no longer a Chicago story; this was a story that no matter where you lived, you turned on the evening news and you would hear about this case.

ARCHIVE (BILL CLINTON RADIO ADDRESS, 9-10-94):PRESIDENT BILL CLINTON: By now, nearly all of us know the story of Robert Sandifer.

JOHN J. DILULIO, JR. (PROFESSOR OF POLITICS, RELIGION AND CIVIL SOCIETY, UNIVERSITY OF PENNSYLVANIA): There was a sense that the country writ large was going to hell in a hand basket. No one had a clear idea of what to do.

NARRATION: Political scientist John DiIulio taught at Princeton and had done extensive research in prisons studying the criminal justice system. From 1984 to 1994, when Sandifer was killed, teenage homicide rates had more than doubled.

JOHN J. DILULIO, JR.: It seemed like there was a high-profile, major, heinous crime in the news almost every day or every week. Random, senseless violence.

ARCHIVAL (NBC, 2-2-93):TOM BROKAW: Teenage killers. The homicide rate for juveniles has now surpassed the rate for adults in this country.

NARRATION: Dilulio looked at studies that estimated that by 2000 there would be a million more teens between the ages of 14 and 17, and he predicted crime rates would snowball even more.

JOHN J. DILULIO, JR.: Youd have a doubling or a tripling in the rate of youth violence in the time between the mid 90s and up to the through mid 2000s.

NARRATION: Perhaps most troubling to DiIulio was what he saw as an indication that the small percentage of kids who commit the most violent crimes would be much more destructive than the generation before them.

JOHN J. DILULIO, JR.: Studies found that essentially 6% of every male youth cohort was responsible for about 50% of all the violent crimes committed by that cohort. That small fraction of people is going to be able to wreak incredible havoc.

NARRATION: Dilullio wasnt the only one predicting a surge in crime.

ARCHIVAL (CBS, 9-22-95):JAMES FOX: By the year 2005, we may very well have a bloodbath of teenage violence.

NARRATION: Northeastern University criminologist James Fox says his choice of words was deliberate.

JAMES FOX (PROFESSOR OF CRIMINOLOGY, NORTHEASTERN UNIVERSITY): I did sound an alarm and I did use some rather strong language in terms of what might happen if we didnt react quickly.

NARRATION: Fox and Dilulio felt compelled to call attention to this perceived problem. Dilulio, an Ivy League academic from South Philadelphia, wrote this article for The Weekly Standard in 1995.

JOHN J. DILULIO, JR.: The term superpredetor originated from an inmate who said as almost a throwaway line, he said Oh, these kids, theyre stone cold predators.

ARCHIVAL (CBS, 4-9-96):JOHN J. DILULIO, JR.: A superpredator is a young, juvenile criminal who is so impulsive, so remorseless, that he can kill, rape and maim without giving it a second thought.

NARRATION: And like a match to a flame, the word caught on.

ARCHIVE (ABC, 6-19-96):HERBERT HOELTER: Superpredator

ARCHIVE (ABC, 6-18-96):GIANNINI: Predator

ARCHIVE (NBC, 2-15-96):FRANCIS: Predators

ARCHIVE (CBS, 4-9-96):BERNIE GOLDBERG: Superpredators

NARRATION: Linguist Ben Zimmer is the language columnist for The Wall Street Journal.

BEN ZIMMER (LANGUAGE COLUMNIST, THE WALL STREET JOURNAL): When you use a word like predator, it is loaded with certain assumptions about the way that an animal hunts another animal. So to call someone a superpredator really amps that up even more.

ARCHIVE (CBS, 4-9-96):JOHN J. DILULIO, JR.: Were talking about a group of kids who are growing up essentially fatherless, Godless and jobless.

NARRATION: Dilulio says that race wasnt pointing to any particular racial group as being the most potentially violent, but in 1996 he wrote that as many as half of these juvenile superpredators could be young, black males.

BARRY KRISBERG: Race was the central issue. That as the number of minority children, principally African American, but also Latino children, that to the extent that that number was increasing in the society, with them would come a big crime increase.

BEN ZIMMER: Whats required in moral panic, is the identification of a particular group of people who are demonized in some way.

BARRY KRISBERG: When you describe another group as Godless you can do anything to them.

NARRATION: Lawmakers seized the moment to spur on the overhaul a legal system they considered too lax.

ARCHIVAL (CNN, 7-16-96):BOB DOLE (PRESIDENTIAL CANDIDATE): Kids that once stole hubcaps, now rape and murder. No fear of punishment. Experts call them superpredators.

ARCHIVAL (CSPAN):HILLARY CLINTON: They are not just gangs of kids anymore. They are often the kinds of kids that are called superpredators. No conscience, no empathy.

ARCHIVAL (CSPAN, 2-15-94):NEWT GINGRICH: There are no violent offenses that are juvenile. You rape somebody, youre an adult. You shoot somebody youre an adult.

BARRY KRISBERG: Virtually every state, almost 45 states, enacted laws cracking-down on juvenile offenders, making it easier to prosecute youth in adult criminal courts, increase penalties.

NARRATION: But at the same time the laws were being enacted, juvenile crime rates were already starting to show a surprising trend.

BARRY KRISBERG: Juvenile crime rates have been plummeting during this period of time in the wake of this panic.

NARRATION: The drop in juvenile crime has been the attributed to many things a stronger economy, better policing, a decline in crack cocaine use. But Dilulios research had not foreseen any of these trends.

JOHN J. DILULIO, JR.: We were at the precipice of being able to explain and predict all kinds of things. Poverty trends, crime trends and so forth. None of that work, none of those predictions in any of those fields have born fruit.

NARRATION: By the late 1990s, after a steady decline in juvenile crime. Dilulio could see just how mistaken he was.

JOHN J. DILULIO, JR.: The predictions were off by a factor of four. It had doubled and it was supposed to double again and instead it was halved, right, and so that is about as far off as one could possibly get. The superpredator idea was wrong. Once it was out there though, it was out there. There was no reeling it in.

NARRATION: The experience was a turning point. Dilulio would go on to work in the Bush administration as Director of Faith-Based and Community Initiatives.

JOHN J. DILULIO, JR.: I lost faith in social science prediction at about the same time that I gained faith of a traditional religious kind. I went to religion and public affairs for the same reason I went to, you know, crime and corrections policies, that I thought that was where the most important issues and where the most good could be done.

NARRATION: But Krisberg says Dilulios turnaround came too late to reverse the damage.

BARRY KRISBERG: It was a myth, and unfortunately it was a myth that some academics jumped onto. The fear over the superpredator led to a tremendous number of laws and policies that we are just now recovering from.

NARRATION: In 2012, a case challenging mandatory life-without-parole sentences for juveniles made it to the Supreme Court. A brief filed in support of the case denounced the superpredator theory. It was a public repudiation, yet Fox and Dilulio both signed on.

JOHN J. DILULIO, JR.: I signed the amicus brief. I thought that although the arguments were a bit one sided, it came to the right conclusion. And so I signed it. Because at the end of the day, its whats going to matter most. What did you do and why did you do it? And did it make a positive difference?

NARRATION: The Supreme Court agreed with Dilulios side.

ARCHIVAL (CBS 6-25-12):SCOTT PELLEY: Automatic mandatory life sentences the justices said, amounted to cruel and unusual punishment.

NARRATION: The court recently ruled that decision would apply retroactively to the more than 2,000 people already serving mandatory life sentences for crimes they committed as juveniles

ARCHIVAL:MAN: I made a bad choice.

NARRATION:citing research showing that teenagers brains arent fully developed, making them less culpable for their actions.

ARCHIVAL (NBC 10, 11-20-16):ANCHOR: The justices wrote that a young persons immaturity reduces their accountability. Juveniles have an inability to assess consequences, are often rash, and are prone to risk-taking things that should be considered when sentencing.

NARRATION: In 2016, Derrick Hardaway was released on parole, after serving nearly 20 years in prison for his role in the death of Robert Sandifer.

DERRICK HARDAWAY: When I got sentenced, being told youve got to do more time in prison than you actually lived at the time, thats harsh, especially for a 16-year-old, to accept.

NARRATION: John Dilulio has worked with three White House administrations to try to implement faith based initiatives in needy communities. But he says hes out of the business of forecasting.

JOHN J. DILULIO, JR.: Demography is not fate and criminology is not pure science. And that lesson, I think this episode from 20 years ago and I think many, many other things in public policy, we should carve that in stone and put it above every research institution and every foundation.