It's hard to know what to make of the just-published Justice Department report on juvenile delinquency. Many of its conclusions are not only controversial but virtually unbelievable, flying in the face of experience, social science and common sense.

For instance: there is no particular link between juvenile lawlessness and adult crime for whites, but the connection does exist for inner-city blacks. Youthful offenders who are punished for their offenses are far likelier to go on to commit more, and more serious, offenses than those who are not. Youngsters who hold after-school jobs are more likely to get into trouble with the law than those who don't.

Can these findings be true? And if they are, what are their implications for public policy?

"Much of the concern about juvenile delinquency has been based on the premise that it leads to adult crime," said Lyle W. Shannon, who directed the seven-year study in Racine, Wis. He found that while "there is some relationship between juvenile delinquency and adult criminality, the relationship is not sufficient to permit prediction from juvenile misbehavior of who will become adult criminals. Furthermore, to the extent that a relationship exists, it may be explained by the operation of the juvenile and adult justice systems as well as by continuities in the behavior of juveniles."

In other words, early identification and intervention, calculated to disrupt delinquent behavior before it becomes a hard pattern, may have the perverse effect of ensuring that the young offenders "will continuously be identified as miscreants."

I am reminded of a study some 10 years ago that showed that even when no sanctions were imposed, the mere fact of being caught by the police tended to lead young offenders into further delinquency. The implication of that earlier study, as I recall, was that simply coming into contact with the law seemed to make young offenders think of themselves as officially bad. It is an interesting point, but hard to translate into policy. Does it mean, for instance, that both the delinquents and the general society are better off if the police don't make the effort to apprehend them?

Equally disconcerting is Shannon's finding that juveniles who work -- the youngsters we tend to think of as responsible and ambitious -- are more likely to get into trouble than those who don't work. Are our common- sense conclusions so wrong? Or is it simply that, given two youngsters equally inclined to flirt with illegality, the one with a job (and the increased mobility that comes from having cash) has more opportunity to get into trouble?

One problem with the study's more controversial conclusions may be the failure of the researchers -- and perhaps of the police -- to distinguish sufficiently between what the youngsters themselves think of as "criminal" behavior and what they consider "fun" (albeit illegal) activity.

As many as half of the Racine youngsters who said they did things that got them, or could have gotten them, in trouble said they did it "just for fun." Could this be another way of saying that these juveniles thought of their occasional activity, but not themselves, as "bad"? Could it be that once the "badness" becomes official, the youngsters are more likely to change their opinion of themselves? Might it not make a difference, for instance, whether a youngster caught with a stolen bicycle is made to return it and apologize to its owner or whether he is booked as a bicycle thief?

Could it be that inner-city youngsters are more likely than their white, suburban counterparts to have their offenses treated as "official" delinquency rather than youthful excess?

And what, finally, are we to make of the fact that most youthful offenders who escaped detection for delinquent behavior had stopped their misbehavior by age 18, or of the fact that only 8 percent said they did so for fear of getting caught? The clear implication is that simple maturation, rather than legal sanction, is the most effective rehabilitative influence.

The conventional wisdom is that it's important to make youthful offenders understand that they can't get away with it, even if it is necessary to lock them up. Shannon reaches a different conclusion:

"The ultimate question is not one of how to most expeditiously remove miscreants from the community but how to integrate them into the large social system so that their talents will be employed in socially constructive ways. This should be a major concern to the community, for if it is not, the cost will become increasingly higher."