Violent Minds

A Breakdown of Every Major Theory

Understanding what drives an individual to commit serial murder remains one of criminology’s most compelling and disturbing questions. While these offenders account for less than 1% of total homicides, their crimes generate outsized public fascination and fear. The answer isn’t simple – research reveals that serial killing emerges from a complex convergence of biological, psychological, environmental, and social factors that interact across a person’s lifetime. This comprehensive exploration examines every major theory that attempts to explain this extreme form of violence.

The Biological Foundation: Brain Structure and Genetics

Brain Abnormalities and Neurological Dysfunction

Neuroimaging studies have revealed striking differences in the brains of violent offenders compared to the general population. Serial killers and other violent criminals consistently show structural and functional abnormalities in key brain regions responsible for emotional regulation, impulse control, and moral decision-making. These abnormalities are frequently discussed in modern analyses of psychopathy vs. sociopathy, where impaired emotional processing and poor behavioral inhibition are central themes.

The prefrontal cortex – particularly the orbitofrontal and ventromedial regions – plays a crucial role in behavioral control, social cognition, and evaluating consequences. This area acts as the brain’s “rational brake,” inhibiting impulsive and aggressive tendencies. When damaged or underdeveloped, individuals experience diminished capacity to control aggressive urges and make morally sound decisions.

Research by Raine and colleagues found that murderers displayed reduced glucose metabolism in the prefrontal cortex, superior parietal gyrus, and corpus callosum, along with abnormal asymmetries in the amygdala, thalamus, and medial temporal lobe. A comprehensive study of 203 homicide offenders highlighted aberrations in gray matter in the orbitofrontal, ventromedial prefrontal, and temporal cortex regions – all areas associated with behavioral control and decision-making.

The amygdala, responsible for processing emotions and fear responses, also shows reduced connectivity with the prefrontal cortex in psychopathic criminals. This disconnection means that processing negative stimuli in the amygdala doesn’t translate into strongly felt negative emotions, which may explain why serial killers don’t feel guilt about their actions or sadness when their victims suffer. This impaired emotional circuit frequently appears in discussions of psychopathy.

Head Injuries: A Critical Risk Factor

Traumatic brain injuries, particularly those sustained during critical developmental periods, emerge as significant risk factors. Research indicates that approximately 80% of high-profile serial killers have suffered significant brain injuries. The timing of these injuries matters enormously – brain injuries before age 5 permanently disrupt the development of foundational brain structures, while injuries during adolescence alter existing behavior and impair impulse control and judgment.

Richard Ramirez suffered two major head injuries before age 5, causing temporal lobe epilepsy and damage to his prefrontal cortex – injuries directly linked to his escalating brutality, sadistic behavior, and impulsive nature. Fred West’s personality changed dramatically after a motorcycle accident at 17 fractured his skull; he immediately became prone to violent rages. John Wayne Gacy developed a blood clot in his brain at age 11 after being hit in the head with a swing, causing blackouts and contributing to later behavioral problems. These cases illustrate the biological vulnerabilities often found in serial killers across history.

One study of juvenile sexual homicide offenders found that all 16 subjects were afflicted with neuropsychiatric vulnerabilities resulting from trauma, lack of oxygen to brain tissues, or infection. Approximately 64% of sexual homicide offenders failed neuropsychological tests – more than double the rate of comparison groups.

Genetic Predisposition: The Hereditary Component

Heritability accounts for approximately 50% of the variance in aggressive behavior. Multiple genes have been identified as contributing to violent tendencies, though none operates in isolation.

The MAOA gene, commonly called the “warrior gene,” codes for the enzyme monoamine oxidase-A, which breaks down neurotransmitters including serotonin and dopamine. Individuals with low-activity variants of this gene show reduced ability to metabolize these neurotransmitters, leading to impaired emotional regulation and increased aggression. A rare point mutation in the MAOA gene resulting in total loss of monoamine oxidase-A was found in multiple generations of a Dutch family exhibiting repeated violent criminal behavior.

The CDH13 gene, associated with neuronal membrane adhesion, has been linked to cases of extreme violence. Significant overlap between MAOA and CDH13 genotypes has been identified in extremely violent offenders. Additionally, polymorphisms in serotonergic genes including SLC6A4, HTR2A, and HTR2B influence serotonin reuptake and signaling, potentially contributing to aggressive criminal behavior.

Research on psychopathic personality traits found that roughly 50% of variance in both fearless dominance and impulsive antisociality was attributable to additive genetic effects. However, genetic predisposition requires environmental triggers to manifest as violent behavior – a concept known as gene-environment interaction.

Neurochemistry: Serotonin, Dopamine, and Hormones

Neurochemical imbalances play a crucial role in regulating aggressive behavior. Low serotonin levels in the brain and reduced concentration of its metabolite 5-HIAA in cerebrospinal fluid have been consistently found in murderers and arsonists. Serotonin acts as the body’s natural “brake system,” modulating behaviors and dampening aggressive drives. When serotonergic function is impaired, this inhibitory control weakens.

Dopamine hyperactivity may secondarily contribute to impulsive aggression. The interaction between deficient serotonin function and excessive dopamine activity in the prefrontal cortex appears to underlie the link between impulsive aggression and violent behavior. Animal studies show that dopamine levels increase while serotonin levels decrease in the prefrontal cortex during and after aggressive episodes.

Hormonal factors also influence violent tendencies. Research demonstrates that individuals with relatively high testosterone and cortisol levels are more likely to engage in impulsive and violent criminal behavior. Testosterone activates subcortical brain areas that produce aggression, while cortisol and serotonin work antagonistically to mitigate these effects. The ratio between these hormones appears critical – psychopathy and aggressive tendencies relate to a high testosterone-to-cortisol ratio.

Childhood Trauma: The Developmental Crucible

The Prevalence of Abuse

Childhood abuse represents one of the most consistent findings in serial killer research. On average, 50% of serial killers report experiencing psychological abuse, 36% physical abuse, and 26% sexual abuse. A landmark study of 50 serial killers found that childhood abuse was significantly more prevalent in lust serial killers, with the type of abuse received influencing later victim choice and behavior.

A comprehensive analysis of 233 male serial killers with known childhood abuse used Behavior Sequence Analysis to demonstrate significant links between specific types of abuse and distinct crime scene behaviors. Sexual, physical, and psychological abuse often led to different patterns of violence, providing individual accounts of how abuse types shape murderous behaviors.

In a study of 62 male serial killers, 48% had been rejected as children by a parent or important figure. This rejection often represents a turning point, as these future killers began diving into self-indulgent fantasies and struggled to understand themselves during puberty. The social experiences that make people dangerous violent criminals are the significant traumatic experiences rather than trivial ones.

Attachment Theory and Maternal Deprivation

Attachment theory – widely regarded as influential in criminological psychology – proposes that healthy development requires close personal bonds formed during the first six months of life. Disruption or absence of this critical bonding period can result in severe behavioral issues in adulthood.

Research suggests a developmental cascade from early parent-child interactions during infancy to violent crimes during adolescence. Maltreated infants face high risk for disturbances of attachment, developing insecure or disorganized attachments that become independent risk factors contributing to poor developmental trajectories.

Jeffrey Dahmer’s formative years were marked by his mother’s anxiety, drug abuse, and periods of absence from the family home – factors that attachment theorists suggest broke the bond with baby Jeffrey and helped shape the psychotic killer he became. Aileen Wuornos was abandoned by her parents and raised by uncaring, sexually abusive grandparents, unable to attach to any primary caregiver. By adulthood, she had little understanding of what healthy relationships looked like.

The OTHA Complex – referring to the orbito-frontal cortex, medial temporal lobes, hippocampus, and amygdala – is implicated in both depraved behavior in violent criminals and in maternal deprivation studies of institutionally-reared children. This neurobiological connection suggests early attachment disruption physically alters brain development in ways that predispose individuals to violence.

The Cycle of Violence

Childhood violence exposure creates a “cycle of violence” where victims of childhood maltreatment become more likely to demonstrate violence later in life. Parents who abuse their children physically and psychologically instill an almost instinctive reliance upon violence as a first resort to any challenge.

A National Institute of Justice study found that childhood abuse heightened risk for criminal behavior in adulthood by encouraging antisocial behavior during childhood. Serial killers treated badly during childhood tended to sexually assault their victims before murdering them, while those without childhood abuse histories did not display sexually violent behavior.

Fantasy Development: The Internal Drive Mechanism

The Role of Violent Fantasies

Fantasy serves as the drive mechanism for repetitive acts of sexual violence. A study comparing 25 serial sexual murderers with 17 single sexual murderers found higher prevalence of paraphilias, documented violent fantasies, and organized crime scenes in the serial murderers – supporting the hypothesis that intrusive fantasy life drives serial killing.

During developmental periods, serial killers process highly developed fantasy systems to defend against traumatic reality they cannot accept. As adults, these fantasies allow them to relive trauma with roles reversed – no longer the passive victim but the active aggressor. This role reversal provides momentary mastery over childhood trauma through virtual revenge situations.

With fantasy progression, the virtual world becomes insufficient and the serial murderer needs to transform fantasy into reality. Murder becomes the logical outgrowth and extension of the serial killer’s fantasy life. Fantasy is the drive mechanism for murder, and the act of murder solidifies and reinforces the fantasy.

The Fantasy-to-Reality Progression

Research on sexually sadistic serial killers reveals that during years of fantasy development, imaginings become increasingly elaborate and detailed. The fantasies cover multiple dimensions: relational (how to establish victim relationships), paraphilic (sexual perversions), situational (settings and methods), and victim type (specific characteristics making prey “perfect”).

Just as drug addiction requires increasing doses, serial killers require increasingly frequent murders as fantasies strengthen. Each murder reinforces the fantasy, but the psychological gain diminishes, creating a compulsion to kill again. The cycle mirrors addiction-the serial killer’s obligation to fantasy drives him to murder just as a heroin addict’s need drives theft.

Psychological Theories: Psychopathy and Personality

Psychopathy: The Core Personality Construct

Approximately 85% of serial killers are psychopaths. Psychopathy is characterized by lack of empathy, remorse, and emotional depth combined with superficial charm, manipulativeness, and grandiose self-perception. Not all psychopaths become murderers-they operate in business and politics-but psychopathic traits dramatically increase violence risk.

Psychopathy reflects reduced connections between the ventromedial prefrontal cortex and the amygdala. This dysfunction in crucial social-emotional circuitry represents a stable characteristic of psychopathic offenders. Studies of psychopathy show compromised gray matter integrity in medial frontal, insular, and somatosensory cortices-alterations resembling those found in healthy individuals with psychopathic traits.

Ted Bundy exemplified psychopathic serial killing. Forensic psychologists using the Psychopathy Checklist-Revised found he displayed superficial charm, grandiose self-worth, pathological lying, manipulativeness, lack of remorse, criminal versatility, and parasitic lifestyle. Despite overwhelming evidence, he showed no genuine remorse and continued manipulating media and legal systems until his 1989 execution.

The Dark Triad and Personality Disorders

Ted Bundy likely displayed all three components of the Dark Triad: psychopathy, narcissism, and Machiavellianism. His narcissistic traits included grandiosity (defending himself in court), need for admiration (enjoying media attention), sense of entitlement, interpersonal exploitation, and lack of empathy. His Machiavellian traits involved master manipulation, viewing others as pawns, strategic planning, and calculated predatory aggression.

Eysenck’s theory of criminal personality proposes that criminal behavior links to three personality dimensions: psychoticism (aggression, impulsivity, lack of empathy), extraversion (sociability, risk-taking, need for stimulation), and neuroticism (emotional instability, anxiety). High psychoticism characterizes violent and antisocial behavior. High extraversion-particularly in those with underactive nervous systems seeking excitement-can lead to criminal acts. Bundy exhibited high psychoticism and extraversion but low neuroticism, making him cold and calculating rather than emotionally unstable.

Environmental and Social Factors

Social Learning Theory

Albert Bandura’s Social Learning Theory proposes that criminal behavior is learned through observing, imitating, and modeling others. Individuals don’t need direct contact with criminal models-they can internalize behaviors from symbolic models like media characters, making this theory particularly relevant in today’s digital age.

Richard Ramirez provides a chilling example. Brutally beaten by his father and exposed to graphic violence by his cousin (a Vietnam veteran who showed him photos of torture and rape), Ramirez learned that violence was acceptable and powerful. He observed these models, retained the behaviors, and eventually reproduced them when he believed he had the capability and motivation.

Social Learning Theory operates through four stages: attention (noticing the model’s behavior), retention (remembering the behavior), reproduction (physical and psychological capability to perform it), and motivation (having reason to act, often through vicarious reinforcement). When criminal models are rewarded with money, power, or social praise, observers become more likely to imitate those behaviors.

Socioeconomic Factors and Social Disorganization

Social disorganization theory emphasizes that crime flourishes in communities with breakdown of social control and lack of shared values. In areas with high poverty, instability, or social fragmentation, individuals may become detached from social bonds and community norms, leading to deviant behavior.

Serial killers may emerge from environments lacking social structure needed to prevent violence. Feelings of isolation and detachment from society in disorganized communities contribute to violent behavior. Research on female serial killers shows many came from families struggling financially where parents neglected or abused children.

The Macdonald Triad: Myth vs. Reality

The Macdonald Triad-comprising animal cruelty, fire-setting, and bedwetting-was proposed in 1963 as predictive of future violent behavior. However, extensive research has thoroughly debunked its predictive validity.

A comprehensive 2020 review found that any one triad behavior in isolation could predict future violent offending, but it’s very rare to find all three together as predictors. The empirical research doesn’t substantiate the triad’s premise. Rather, these behaviors better indicate dysfunctional home environments or poor childhood coping skills.

Studies confirm that animal cruelty, fire-setting, and enuresis are products of psychological and physical parental abuse. Children subjected to traumatic experiences need outlets where they can preserve autonomy and control-they exert power by inflicting suffering on animals and express anger by setting fires. These behaviors are reactions to childhood abuse, not reliable predictors of serial murder.

Rational Choice and Decision-Making

Serial Killers as Rational Actors

Contrary to popular perception of serial killers as purely impulsive, research increasingly supports Rational Choice Theory‘s application to understanding their behavior. Serial killers make conscious decisions based on cost-benefit evaluations, weighing rewards against risks of apprehension.

A comprehensive analysis refuted the antiquated idea that serial killers act impulsively, supporting use of Rational Choice Theory to explain offender behavior. Though the act of murder may stem from psychological compulsion, the execution demonstrates rational planning-victim selection, location choice, body disposal, and evidence concealment all reflect calculated decision-making.

Research on body disposal demonstrates this rationality. Serial killers make conscious decisions about disposal locations and methods to avoid capture. Distance traveled, concealment efforts, and whether bodies are left exposed all reflect strategic choices aimed at minimizing detection risk.

Jeffrey Dahmer exemplifies organized, rational planning despite psychological pathology. Forensic examination revealed he selected easy targets from bars, posed with victims as souvenirs, and maintained storage containers for bodies-all evidence of calculated behavior designed to maximize gratification while minimizing capture risk.

The Organized vs. Disorganized Dichotomy

The FBI’s Crime Classification Manual categorizes serial killers as organized, disorganized, or mixed. This typology, developed through interviews with 36 convicted sexual murderers, revealed distinct crime scene and background differences.

Organized offenders display average or above-average intelligence, social competence, and live with partners. They plan crimes carefully, use restraints, transport victims, and conceal bodies. They show forensic awareness, rarely leaving incriminating evidence. Their crimes reflect semblance of order before, during, and after offenses. They may revisit crime scenes or interact with law enforcement to feel superior.

Disorganized offenders are typically below-average intelligence, socially inadequate, and sexually incompetent. They commit crimes suddenly without planning, use weapons of opportunity, and leave victims where killed. Crime scenes are messy with evidence left behind. These offenders act in confused, distressed states with no forensic awareness.

Most killers demonstrate mixed characteristics because human psychology is dynamic and changes with experience. An organized killer may lose control momentarily, while disorganized killers may occasionally plan. The dichotomy provides useful framework but oversimplifies the complexity of serial murder.

Motivational Typologies

Holmes and DeBurger Classification

The most familiar typology proposes four types based on driving motivations: visionary (responding to voices/visions), mission-oriented (eliminating “undesirable” groups), hedonistic (deriving pleasure), and power/control-oriented (dominating victims).

Hedonistic killers subdivide into lust killers (sexual gratification), thrill-seekers (excitement from killing), and comfort killers (material gain). Lust murder becomes addictive and triggers escalation. Examples include John Wayne Gacy, Jeffrey Dahmer, Ted Bundy, and Edmund Kemper. These killers often have paraphilias-Peter Kurten drank blood, Joachim Kroll consumed parts of children.

The Motivation Debate: Sex, Power, or Anger?

Controversy exists regarding what motivates serial sexual killers. Hypotheses range from sexual gratification to power and control to anger expression. Theoretical, empirical, evolutionary, and physiological evidence supports that serial sexual murderers primarily commit crimes in pursuit of sadistic pleasure.

Power and control over victims serve secondary purposes of heightening sexual arousal and ensuring victim presence. Criminal investigations consistently reveal erotically charged crimes with sexual motivation expressed overtly or symbolically. Anger isn’t considered a key motivator due to its inhibitory physiological effect on sexual functioning.

The Zodiac Killer exemplified thrill-seeking – writing that the rush of killing was better than sex. These killers seek excitement from planning and committing crimes rather than sexual gratification. The pleasure connects to power and control of taking life.

Developmental Pathways and Progression

The Seven-Phase Cycle

Research by Joel Norris identified a seven-phase cycle many serial killers experience: Aura, Trolling, Wooing, Capture, Murder, Totem, and Depression.

During the Aura Phase, killers retreat into dark fantasies, losing touch with reality as imaginings intensify. Personality may noticeably change as they transform into who they imagine themselves to be. This phase involves withdrawal from social relationships and drift from reality, often accompanied by violent sexual thoughts and increased substance use.

The Trolling Phase involves formulating murder plans, selecting victims, and for organized killers, choosing body disposal locations. The Wooing Phase sees the killer gaining victim trust through charm or deception – Ted Bundy‘s feigned injuries exemplify this stage.

Capture and Murder phases execute the fantasy. The Totem Phase involves taking trophies or mementos – jewelry, photographs, body parts – that allow reliving the murder. Almost universally, serial killers take something from victims.

Finally, the Depression Phase brings temporary emotional letdown as the reality of murder fails to fully satisfy the fantasy. This depression eventually fuels return to the Aura Phase, restarting the cycle. Serial killers repeat this cycle indefinitely until retirement, capture, or death.

From Fantasy to First Murder

The progression from fantasy to actual killing represents a critical threshold. One study of sexually sadistic serial killers found they had developed and refined violent sexual fantasies about becoming serial killers prior to actualizing their fantasy. These fantasies became increasingly elaborate over years, eventually demanding real-world expression.

The decision-making power over life and death infuses feelings of omnipotence. When delusional fantasies reach their peak, killers feel compelled to enact them, dominating victims and transforming them into objects for pleasure. After the first murder activates a “cyclical mechanism,” the killer enters a circular complex mental process like addiction, leading him to kill again.

Statistics and Patterns

Prevalence and Demographics

The United States leads the world with 3,613 documented serial killers as of 2020 – England, in distant second place, has 176. Between 1990 and 2020, the U.S. registered 12,236 victims of serial killings. California has the highest total with 1,777 victims, followed by Texas with 984 and Florida with 933.

However, per capita rates reveal different patterns. Alaska has the highest rate at approximately 7–8.6 victims per 100,000 residents, followed by Louisiana at 7.47 and Kansas at 6.05. These differences reflect varied population sizes, geographic features, and social dynamics.

Serial killings account for less than 1% of total homicides. The phenomenon peaked between 1970 and 2000, when 70% of recorded serial murders occurred. In the 1970s, nearly 300 serial killers operated in the U.S.; by the 2010s, fewer than 50 were active. This dramatic decline likely reflects improved forensic technology, DNA databases, better inter-agency communication, increased surveillance, and heightened public awareness.

Serial murderers tend to be lone white males. For motivation, 32% killed for financial gain, 25% for pleasure, 18% for anger, and 6% for gang activity. Shooting is the most common method, followed by strangulation and stabbing. Victims are evenly split between males and females with a median age of 30.

Prevention and Intervention

The Fast Track prevention program represents the largest randomized controlled trial testing whether comprehensive early intervention can prevent adult psychopathology and crime. Beginning in 1991 with high-risk 6-year-old children, the program blended parent behavior-management training, child social-cognitive skills training, peer coaching, academic tutoring, and classroom improvements across 10 years at $58,000 per child.

Results demonstrated intervention efficacy in preventing adult psychopathology among high-risk early-starting conduct-problem children. The program reduced aggressive behavior throughout elementary school, delinquent behaviors in high school, and juvenile and adult arrests through age 21. Contrary to models suggesting intervention won’t penetrate highest-risk groups, Fast Track effects were stronger among the highest-risk children than moderate-risk groups.

This provides evidence that early, comprehensive intervention addressing multiple components of antisocial development can have enduring impact on preventing violence. The critical period appears to be childhood and adolescence before patterns solidify.

Treatment Challenges

Rehabilitation of serial killers and psychopaths presents enormous challenges. Traditional rehabilitation methods don’t work well for high-psychopathy offenders – some interventions may even make them more manipulative. Research shows psychopathy scores are significantly associated with poor treatment response and increased recidivism risk.

A seemingly paradoxical outcome shows highly psychopathic individuals receive earlier conditional release despite greater violence history and recidivism likelihood – their cunning interpersonal style makes them adept at deceiving parole boards. There is consensus that psychotherapy and medication are generally ineffective with psychopaths.

However, case studies demonstrate treatment can work when individually tailored with focus on risk management while addressing psychiatric issues. The Mendota Juvenile Treatment Center’s Decompression Model achieved a notable reduction in recidivism among psychopathic youth. This suggests that structured, reward-based programs with clear behavioral contingencies may offer more promise than traditional approaches.

Cognitive-behavioral therapy shows effectiveness in reducing recidivism among violent offenders when matched to offender personality and risk level. The Risk-Need-Responsivity model tailors treatment intensity to risk level, addresses criminogenic needs like impulsivity and aggression, and uses therapy suited to offender personality.

The Convergence Model: Putting It All Together

Serial killing doesn’t result from a single factor but rather the convergence of multiple variables over time. The biopsychosocial model integrates biological vulnerabilities, psychological traits, and social experiences to explain how serial killers develop.

Genetic predispositions (MAOA variants, serotonergic polymorphisms) create biological vulnerability. Prenatal factors, birth complications, or early head injuries disrupt brain development, particularly in prefrontal cortex, amygdala, and temporal lobes. These neurological abnormalities impair impulse control, emotional regulation, and moral reasoning.

Childhood trauma – abuse, neglect, attachment disruption-occurs during critical developmental windows when the brain is most plastic. This trauma interacts with biological vulnerabilities through gene-environment interaction, with MAOA polymorphisms particularly sensitive to childhood maltreatment. Traumatic experiences shape fantasy development as psychological defense mechanisms.

Social learning from violent models (family members, media, peers) provides behavioral scripts for violence. Dysfunctional environments with weak social bonds and disorganized communities fail to provide protective factors. Psychopathic personality traits emerge from this convergence of biological and environmental factors.

Violent fantasies develop and intensify, fueled by paraphilias and increasingly elaborate scenarios. Eventually fantasy becomes insufficient and demands real-world expression. The first murder activates an addictive cycle, with each killing reinforcing fantasies but providing diminishing psychological satisfaction, driving escalation.

Throughout this progression, rational decision-making operates alongside psychological compulsion. Serial killers select vulnerable victims, plan crimes to minimize detection risk, and adapt strategies based on success or near-capture. This explains how they often evade capture for extended periods despite repeated murders.

Conclusion

The question “Why do people become serial killers?” has no single answer. Instead, it requires understanding how biological predispositions, neurological abnormalities, genetic factors, neurochemical imbalances, childhood trauma, attachment disruption, fantasy development, psychopathic personality traits, social learning, environmental stressors, and rational decision-making converge across developmental stages.

While genetic factors may create vulnerability and brain abnormalities may impair regulation, these biological factors alone don’t create serial killers. Environmental triggers – particularly severe childhood trauma during critical developmental periods – appear necessary for violent tendencies to manifest. The interaction between nature and nurture, between biological predisposition and environmental experience, ultimately shapes whether an individual develops into a serial killer.

This comprehensive understanding has practical implications. Early intervention programs targeting high-risk children show promising results in preventing violent outcomes. Improved recognition of warning signs – severe childhood abuse, attachment disruption, emerging violent fantasies, head injuries affecting frontal lobe function – may enable earlier intervention before patterns solidify. However, the complexity of factors involved and individual variation means prediction remains imperfect and prevention challenging.

Understanding serial killers through multiple theoretical lenses – biological, psychological, social, and rational – provides the most complete picture of this devastating phenomenon. While we may never fully comprehend what drives someone to commit such extreme violence, continued research across these domains brings us closer to prevention, earlier detection, and more effective intervention.

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