Let us start where it matters: a thirteen-year-old girl, Katie, was murdered. The one who killed her was a classmate of the same age, Jamie Miller. Adolescence (Netflix, 2025) is not a series about a criminal genius nor about an unfathomable psychopath; it is the portrait, uncomfortable and deliberately ordinary, of how an ordinary boy comes to stab a classmate after months steeping himself in the so-called manosphere: that archipelago of forums, videos and chats where incel resentment toward women circulates. The question the fiction leaves hanging is not "how could he be born like that?", but something more disturbing: where did he learn it?. And for that question criminology has an answer almost a century old: the theory of differential association.
// The theoryCrime is learned, and so are its excuses
In 1939, Edwin Sutherland broke the false dilemma between the criminal who is "born" and the one who "calculates" with a third path now taken for granted: criminal conduct is learned in interaction with other people, above all in intimate groups. What is decisive about his differential association is what is learned: not only techniques, but also motives, attitudes and justifications. One offends, he said, when the definitions favorable to breaking the rule that one has internalized outweigh the unfavorable ones —the proportion of messages, their intensity and the age at which they arrived all count—. Later, Gresham Sykes and David Matza put a name to those definitions with their techniques of neutralization: the denial of the victim ("she deserved it", "they humiliate us first"), the denial of the harm, or the appeal to a higher loyalty ("I defend real men"). The thesis applied to Jamie is clear-cut: no one is born despising women; that contempt, and the script to justify it, was transmitted to him the way a trade is transmitted.
The manosphere as a delocalized classroom
Sutherland thought of physical groups: the gang, the street corner, the pickpocket's workshop. His theory, however, has gained an unexpected relevance in the digital age, because the "intimate group" now fits inside a screen. The manosphere works like a classroom without walls, open 24 hours: algorithms that chain a "motivational" video to another ever more hostile one, forums where a lonely kid finally finds a "we", influencers who sell resentment as lucidity. There one learns a vocabulary (the division of the world into sexual winners and losers), a worldview (woman as enemy or as prize) and, above all, the alibis that armor the conscience before acting. Jamie did not receive a teacher with a face: he received thousands of micro-messages, repeated, intense and early, that gradually tipped the balance. The physical proximity that Sutherland considered key is today replaced by saturation: an incessant flow of definitions favorable to hostility. The process of incel radicalization that Adolescence narrates is, read this way, differential association in its purest form.
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// The subjectA pupil, not a monster
The most unsettling thing about Jamie is how ordinary he is. There is no great flaw, no cinematic origin story: there is an insecure thirteen-year-old, somewhat invisible in class, who seeks to belong and finds a group that offers him a flattering account of his malaise —you are not the problem, they are—. The series shows the learning in its layers: the language he repeats without fully understanding it, the emotional hierarchy he has absorbed, the ease with which he turns a classmate's rejection into a collective grievance. When, in the interrogation, he denies and lashes out, we are not witnessing the cunning of an experienced criminal, but the techniques of neutralization already installed: he minimizes the harm, shifts the blame onto the victim, presents himself as the one truly wronged. That is the imprint of the digital classroom. And it must be said plainly: reconstructing how he learned does not dilute his responsibility by one gram. Jamie took the knife. Jamie killed Katie. The learning explains the trajectory; it does not erase the one who traveled it, nor, far less, the one who suffered it.
Jamie Miller
// The decisive nuanceRisk is not destiny
Here is the line that cannot be crossed. That online misogyny is a risk factor does not make it a mechanical cause. Millions of adolescents look into those same forums and videos, and the overwhelming majority attack no one: exposure is not a button that manufactures murderers. Differential association was never deterministic; it speaks of probabilities that depend on the proportion of messages, on which other influences they compete with (a present family, healthy friendships, a teacher who listens) and on the individual differences that the theory itself acknowledges it does not fully explain. Precisely for that reason it is a tool of prevention, not an alibi: if what weighs is the balance of definitions, then it matters enormously which contrary messages a kid receives, who speaks to him and when. The lesson of Adolescence is not "screens kill", a phrase as comfortable as it is false; it is that the digital classroom has begun to give lessons in hatred to minors and that, faced with it, the silence of adults is not neutral.
// The crackExplaining the learning is not exonerating the murderer
The theory has cracks that Jamie's case illuminates. The first, already known: differential association does not explain the first teacher (from whom did the manosphere gurus learn?), nor does it clarify why, of two boys exposed to the same flow, one sinks and the other passes by —the individual differences, temperament, biography are missing—. Nor does it measure those slippery "favorable definitions" well. But the most dangerous crack is not theoretical, it is moral: using the learning as an alibi. "The internet radicalized him" can slide toward "then it is not his fault", and there the explanation is perverted into an excuse. Sutherland analyzed structures of learning precisely to pinpoint responsibility with more precision, not less: understanding that Jamie internalized a hostile script does not turn him into an innocent automaton, but into an agent who made that script his own and acted. To explain is not to exonerate.
There is a second temptation, symmetrical and also deceptive: to dismiss Jamie as an isolated monster, an inexplicable anomaly, so as not to look at the classroom that educated him. Reducing him to "a bad kid" reassures us, but it blinds us to what the series wants us to see —an industry of resentment that monetizes the loneliness of adolescents and sells them contempt as identity—. The honest reading holds both things at once: Jamie is fully responsible for having killed Katie, and that crime grew in an ecosystem that normalized hostility long before the first blow. And at the center, always, the only remembrance that matters: that of Katie, the girl whom a learning of hatred erased from the world, and that of her family. Not the murderer's.
Watching which classroom our own frequent
Jamie Miller matters because he transfers a theory from 1939 to the most contemporary problem there is: the emotional and moral education of minors has stopped happening only at home and at school. If attitudes are learned in interaction, today a good part of that interaction happens on screens designed to hold attention at any price, including that of escalating toward the most extreme content. The prevention that differential association suggests is not to prohibit or demonize, but to compete for the balance of definitions: to be present, to talk about the subject without panic or sermon, to offer belonging and better stories than those of resentment, and to teach how to recognize a moral alibi when they have one in front of them. What has been learned can be relearned —that is the hope beating within the whole theory—. But relearning requires that some adult occupy the place that today, too often, an algorithm fills in silence. The question Adolescence leaves is not only what Jamie did, but which classroom the children close to us frequent, right now.
Three key takeaways
- Jamie Miller (Adolescence) illustrates Sutherland's differential association: misogynistic contempt and the justifications that sustain it are neither inherited nor calculated, they are learned. The manosphere acts as a delocalized 24/7 classroom where those "favorable definitions" toward hostility saturate a vulnerable minor.
- Risk is not destiny. Exposure to online misogyny is a risk factor, not a mechanical cause: the vast majority of those exposed never attack anyone. The theory speaks of probabilities and of a balance of messages, not of a button that manufactures murderers.
- To explain is not to exonerate. Reconstructing how Jamie learned pinpoints his responsibility with more precision, not less, and forces us to look at the ecosystem that educated him. The remembrance is for Katie and her family, never for the murderer.
Sources · further reading
- Sutherland, E. H. (1947). Principles of Criminology (4ª ed.). Lippincott.
- Sykes, G. M. & Matza, D. (1957). «Techniques of Neutralization». American Sociological Review, 22(6).
- Akers, R. L. (1973). Deviant Behavior: A Social Learning Approach. Wadsworth.
- Bates, L. (2020). Men Who Hate Women. Simon & Schuster.
- Warr, M. (2002). Companions in Crime: The Social Aspects of Criminal Conduct. Cambridge University Press.
Case-file questionsFrequently asked questions
¿Quién es Jamie Miller?
Jamie Miller es un villano de Adolescence, analizado en KRIMINIS con la lente de la criminología. Katie is dead. She was murdered by a thirteen-year-old classmate. Before the knife came months of screen: forums, videos and chats where someone, faceless, taught him to see girls as enemies. He was not born hating: he learned it. That is the uncomfortable part.
¿Por qué Jamie Miller se convierte en villano?
Jamie Miller and differential association: a thirteen-year-old is not born despising women, he learns it. The manosphere as a delocalized classroom where both the resentment and the alibis to justify it are transmitted at once.
¿Qué teoría criminológica explica a Jamie Miller?
El caso de Jamie Miller se analiza desde la Asociación diferencial. The theory of differential association (Sutherland) holds that criminal conduct, and the attitudes that sustain it, are learned in interaction with others. Jamie Miller, from the series Adolescence (Netflix, 2025), is a thirteen-year-old who murders a classmate after being radicalized in the incel manosphere. This case file reads his story as a process of learning: not an innate monster, but an adolescent who internalizes, in a 24/7 digital classroom, both misogynistic resentment and the moral alibis that neutralize it. Online misogyny is a risk factor, not a mechanical cause: the vast majority of those exposed never attack anyone. Explaining that learning is not exonerating the murderer; the remembrance is for Katie.
