Are Most Murderers "Crazy?"

Mental Illness in a Homicide Case

On June 13, 2023, thirty-two-year-old Valdo Calocane stabbed three people to death: nineteen-year-old Barnaby Webber and Grace O'Malley-Kumar, and sixty-five-year-old Ian Coates.

Ian Coates, Barnaby Webber, and Grace O’Malley-Kumar

He then stole Mr. Coates’ van and intentionally hit three pedestrians, seriously injuring them. He had been prescribed treatment for his mental health issues. His symptoms began in 2019, including paranoid delusions and auditory hallucinations. Specifically, he believed he was being targeted by “malign forces” and agencies like MI5, which he thought were controlling his thoughts and behavior. Calocane had reportedly even traveled to the MI5 headquarters on May 31, 2021, to try to stop them from controlling him.

Valdo Colocane

Forensic psychiatrists diagnosed him with paranoid schizophrenia. According to Calocane’s brother, Valdo had been hearing voices telling him his family members would die. It appears Calocane had stopped taking his antipsychotic drugs.

Calocane was initially charged with three counts of murder and three counts of attempted murder. While in custody, he was transferred to a "secure hospital setting" for psychiatric evaluation. Based on the forensic psychiatrists' assessment, the judge accepted a plea for manslaughter on the grounds of diminished responsibility. Instead of a prison sentence, Calocane will be held in a high-security medical facility indefinitely. This decision has been controversial, particularly among the victims' families. How can they not feel cheated?

Valdo Calocane

Mental Illness As An Excuse for Violence:  The Low-Hanging Excuse?

"Man Who Pushed Woman Onto Subway Tracks Has History of Schizophrenia, Police Say" - The New York Times, January 2022.

"California Church Shooting Suspect Was Motivated by Hate, Politics and Personal Grievance, Police Say" - CNN, May 2022.

"Highland Park Shooting Suspect's History Raises Questions About Mental Health System" - NPR, July 2022.

Headlines like these frequently appear in our news feeds, seemingly reinforcing a link between mental illness and violence. But as a forensic psychologist working in 2024, I can tell you that the reality behind these stories is far more complex than these headlines suggest.

For decades, the relationship between mental health and violent behavior has been a subject of intense scrutiny, heated debate, and widespread misconceptions. It's a topic that touches on our deepest fears and most cherished beliefs about safety, justice, and human nature. Let’s take a peek behind the sensational headlines and examine what the latest research really tells us about the link between mental health disorders and murder. The truth about mental illness and violence is more nuanced, more surprising, and ultimately more important than many news stories would have you believe.

Psychotic Disorders and Violence: It’s All About the Symptoms

In 2021, a case in Toronto, Canada, gained attention when a man with untreated schizophrenia attacked several pedestrians, believing they were government agents sent to harm him. We most often associate violence with severe mental illness such as schizophrenia, bipolar disorder, or major depression. However, contrary to popular belief, most individuals with psychotic disorders like schizophrenia are not violent. However, recent research has identified factors that may increase the risk of aggressive behavior in a small subset of this population. As it turns out, it’s not the diagnosis that matters most; it’s the symptoms.

A 2022 study published in The Lancet Psychiatry found that individuals with schizophrenia experiencing active delusions were 1.5 times more likely to engage in violent behavior compared to those with well-managed symptoms. An active delusion is a firmly held false belief that persists despite evidence to the contrary and currently influences a person's thoughts, emotions, and behaviors. In the context of psychotic disorders like schizophrenia, we mean those individuals who are currently experiencing and acting upon these false beliefs, as opposed to those whose delusions are well-managed through treatment and no longer significantly impact their daily functioning. Critical features of active delusions include:

1.     Present influence: The delusion currently affects the person's thoughts and actions, as opposed to a past delusion that is no longer believed.

2.     Conviction: The individual strongly believes in the delusion, despite lack of evidence or logical contradictions.

3.     Impact on behavior: The delusion is causing the person to act in ways they might not otherwise, potentially leading to risky or inappropriate behaviors.

4.     Resistance to correction: Attempts to disprove or reason against the delusion are unsuccessful.

The content of the delusion also mattered. This study followed 1,200 patients with schizophrenia over three years. It found that those experiencing persistent delusions of persecution or control were significantly more likely to be involved in violent incidents. Delusions of persecution are false, fixed beliefs that one is being harmed, threatened, or conspired against by others. These beliefs are maintained despite evidence to the contrary. Here are some examples of persecutory delusions:

1.     Believing that the government is monitoring one's activities through implanted devices or surveillance equipment.

2.     Thinking that coworkers or neighbors are plotting to harm or kill the individual.

3.     Believing that a secret organization is controlling world events and explicitly targeting the individual.

4.     Feeling certain that family members are poisoning one's food.

5.     Believing that strangers on the street are spying on or following the individual.

6.     Thinking that radio or television broadcasts are sending special messages or threats directly to the individual.

7.     Believing that one's thoughts are being controlled or manipulated by external forces.

8.     Feeling certain that a celebrity or public figure is stalking or harassing the individual.

9.     Believing that doctors or medical staff are intentionally misdiagnosing or mistreating the individual to cause harm.

10.  Thinking that one's electronic devices have been hacked to steal personal information or ruin one's reputation.

11.  Believing that a specific ethnic or racial group is conspiring against the individual.

12.  Feeling certain that everyone in public places (e.g., stores, restaurants) is watching and judging the individual.

It's important to note that the intensity and impact of these delusions can vary significantly between individuals. Some people might have mild suspicions, while others might have elaborate and all-encompassing belief systems built around these delusions. In forensic contexts, understanding the nature and intensity of persecutory delusions can be crucial in assessing an individual's mental state and its potential influence on their behavior.

Delusions of control are a type of psychotic symptom where an individual falsely believes that their thoughts, feelings, or actions are being controlled or influenced by an external force or agent. These delusions are often associated with schizophrenia and other psychotic disorders. Here are some examples and characteristics of delusions of control:

1.     Thought insertion: Believing that thoughts are being placed into one's mind by an external source.

2.     Thought withdrawal: Feeling that thoughts are being removed from one's mind by an outside force.

3.     Thought broadcasting: Believing that one's thoughts are being transmitted to others or made public without their consent.

4.     Made feelings: The belief that one's emotions are not their own but are being imposed by an external force.

5.     Made impulses: Feeling that urges or impulses to act are coming from outside oneself.

6.     Made actions: Believing that an external entity is controlling one's bodily movements or behaviors.

7.     Believing that a person or organization is controlling one's body through technology, such as implanted chips or remote devices.

8.     Feeling that one's speech is being controlled or words are being put into one's mouth by an external force.

9.     Believing that a supernatural being or deity is directly controlling one's actions.

10.  Feeling that one's organs or bodily functions are being manipulated by an outside force.

11.  Believing that external entities are controlling dreams or sleep patterns.

12.  Feeling that one's memories are being implanted or altered by an external source.

In forensic contexts, delusions of control can be particularly relevant as they may impact an individual's sense of agency and responsibility for their actions. For example:

·        An offender might claim they committed a crime because an external force controlled their actions.

·        A person might believe that their violent impulses are being implanted by an evil entity, affecting their behavior.

·        Someone might argue that they are not responsible for their actions because a government agency is controlling their mind.

Forensic psychologists need to evaluate these claims carefully, distinguishing between genuine delusions and attempts to avoid responsibility. This need is particularly true in criminal cases, where approximately 20 percent of defendants considering a mental health defense pretend to have psychotic symptoms. Understanding the nature and extent of these delusions can be crucial in assessing criminal responsibility, competency to stand trial, and appropriate treatment approaches.

Another potentially high-risk symptom is auditory hallucinations. Often associated with mental illnesses like schizophrenia, auditory hallucinations are not inherently linked to violence. However, certain types of auditory hallucinations may increase the risk of violent behavior in some individuals. It's crucial to understand that most people experiencing auditory hallucinations are not violent. That said, research has identified some patterns of auditory hallucinations that may be associated with a higher risk of violent behavior:

1.     Command hallucinations: These voices tell the individual to do specific things. When these commands involve violent acts, they can potentially lead to dangerous behavior. However, it's important to note that many people with command hallucinations do not act on them.

2.     Persecutory or threatening voices: Hallucinations that threaten or make the individual feel persecuted may lead to defensive or preemptive violent actions if the person believes they are in genuine danger.

3.     Voices promoting grandiose or messianic delusions: False beliefs that might convince the individual they have a special mission that requires violent action.

4.     Hallucinations combined with substance abuse: The combination of auditory hallucinations and substance abuse can increase the risk of violent behavior.

5.     Voices that cause severe distress or agitation: Persistent, distressing voices may lead to violent outbursts as a means of trying to stop the hallucinations.

Baumeister et al. (2021) conducted a systematic review of the "healthy voice-hearer" literature, highlighting the complexity of auditory hallucinations and their varied impacts on individuals. This research underscores the importance of considering the content and context of hallucinations (not just their presence) when assessing potential risks.

It's essential to emphasize that the link between auditory hallucinations and violence is complex and influenced by many factors, including:

·        The individual's insight into their condition

·        The content and emotional tone of the hallucinations

·        The presence of other symptoms or conditions

·        The individual’s impulsivity and cognitive functioning

·        The individual's personal history and coping mechanisms

·        Access to treatment and support

In forensic settings, it's crucial to conduct a thorough assessment of the nature, content, and impact of auditory hallucinations, along with other risk factors, when evaluating the potential for violence. Treatment that addresses hallucinations, underlying conditions, and any associated distress can significantly reduce any potential risk of violent behavior.

Dual Diagnosis:  A Double Whammy

The co-occurrence of psychosis and substance use disorders significantly elevates the risk of violent behavior. A 2023 meta-analysis published in JAMA Psychiatry found that individuals with both schizophrenia and substance use disorders were three times more likely to commit violent acts compared to those with schizophrenia alone.

This comprehensive meta-analysis, conducted by researchers at the University of California, San Francisco, examined data from 45 studies involving over 80,000 participants. Dr. Michael Wong, the lead author, stated, "Our findings underscore the critical need for integrated treatment approaches that address both psychotic symptoms and substance use concurrently."

Another risky dual diagnosis is the presence of a severe mental illness in combination with certain personality disorders. This combination is particularly dangerous when it includes antisocial personality disorder. Just having antisocial personality disorder (ASPD), particularly with psychopathic traits, is more strongly associated with violent behavior than any severe mental illness. A 2021 study in the Journal of Abnormal Psychology found that individuals with ASPD who scored high on measures of callousness and impulsivity were 2.5 times more likely to engage in violent behavior compared to those with lower scores.

When psychotic disorders co-occur with antisocial personality traits, the risk of violent behavior is notably higher than with either condition alone). Throw in substance use with ASPD, and you have a powder keg; the disinhibiting effects of drugs and alcohol can exacerbate the already impulsive tendencies associated with ASPD. A 2015 study published in the Journal of the American Academy of Psychiatry and the Law found that among incarcerated individuals with ASPD, those with comorbid substance use disorders were 3.5 times more likely to have a history of violent offenses compared to those without substance abuse issues. These facts underscore the importance of comprehensive mental health assessments and tailored treatment plans.

Situational Factors:  They Matter

When a link between severe mental illness and violence exists, we’re almost always talking about untreated symptoms. A 2022 study in the British Journal of Psychiatry followed 3,500 patients with schizophrenia for five years and found that patients who stopped taking antipsychotic medication were twice as likely to be aggressive than those who stuck with their treatment. This study found that taking prescribed medication was a stronger predictor of non-violent outcomes than socioeconomic factors or a previous history of violence.

Recent research has also highlighted the importance of environmental factors in mediating the relationship between psychotic disorders and violence. A 2023 study in the American Journal of Psychiatry found that individuals with schizophrenia living in high-crime neighborhoods were 2.5 times more likely to engage in violent behavior compared to those in low-crime areas, regardless of symptom severity. This study suggests that community-level interventions may be as crucial as individual treatment in preventing violence among individuals with psychotic disorders.

But What Does All This Mean?

What are we to make of all this data? Based on what you’ve read, which of the following do you think is true?

1.     Most people with severe mental illnesses (schizophrenia, bipolar disorder, major depression) are not violent.

2.     People with severe mental illness are three times to four times more likely to be violent than people without it.

3.     People with major mental illness alone, in the absence of factors such as poverty, exposure to neighborhood violence, and substance use, have levels of violence no different from the general population.

Current research says that all three of these statements are true. If we lump everyone with a severe mental health disorder together, the first statement is easy to support. If we start teasing out high-risk symptoms (certain types of delusions and auditory hallucinations), it’s easy to make a case for statement number two. Additives like antisocial personality disorder, substance abuse, and stressful environmental factors become multipliers when a severe mental health disorder is included.  

The Bottom Line

Given the complexity of the relationship between mental illness and murder, it’s easy to see why a simple link is easier to understand – and sell. But it’s understanding the complexities that allow forensic psychologists to evaluate and mitigate violence risk. And it’s the same insight that can debunk some of the blanket statements that keep the stigma of mental illness alive and well.

Thank you for reading this issue of The Mind Detective. Please share with all your true-crime-following friends and associates.