The Correlation Of Serial Killers And Mental Illness

This essay sample was donated by a student to help the academic community. Papers provided by EduBirdie writers usually outdo students' samples.

Cite this essay cite-image

Table of contents

  1. Introduction to Serial Killers and Mental Illness
  2. Understanding Schizophrenia in Serial Killers
  3. Case Studies: The Son of Sam and Cosmo DiNardo
  4. Antisocial Personality Disorder and Psychopathy in Serial Killers
  5. Conclusion: Recognizing Symptoms and Providing Help
  6. References

Introduction to Serial Killers and Mental Illness

Throughout the years, mental illness and the crimes, more specifically the methodology, of serial killers have often gone hand in hand with one another. There are various speculations that the people who do have a mental illness, such as schizophrenia and antisocial personality disorder, are more prone to committing moral atrocities. While this could be true in some cases, like with the Son of Sam, who was a serial killer in the late 70’s and was responsible for the deaths of multiple women, he was diagnosed with schizophrenia. He was convinced that his dog was persuading him to kill women, and that demons were shouting profanities at him. Like the Son of Sam, another current case can be linked to his. A twenty-year-old named Cosmo DiNardo, claimed he saw visions of killing people, and like his predecessor, he brutally killed six individuals in a short span of under five years. Another infamous man who embodied another stereotype of mental illness, more specifically antisocial personality disorder, was Ted Bundy, who was yet another serial killer in the 1970’s, who manipulated and murdered young women. While some accusations of people may be true, there are millions of people who walk around every day with schizophrenia and antisocial personality disorder, and they never think about killing people, nor would they ever want to.

Understanding Schizophrenia in Serial Killers

Schizophrenia is labelled as a “chronic and severe mental disorder that affects how a person thinks, feels, and behaves. People with schizophrenia may seem like they have lost touch with reality. Although schizophrenia is not as common as other mental disorders, the symptoms can be very disabling” (NIH, 2019). Besides Antisocial Personality Disorder, Schizophrenia seems to be one of the top diagnoses when evaluating a serial killer’s cognitive processes. This seems to be the case because when a psychologist sits down to speak with the murderer, a lot of them claim that they heard “voices”, such as angels, The Devil himself, animals, or regular disembodied figures telling them to do it. However, before someone really knows how to diagnose a serial killer with Schizophrenia, they must know the symptoms and how to tell it apart from other disorders. A lot of people also get confused or they misinterpret the symptoms when it comes to the differentiation between Schizophrenia and another mental illness known as DID, or Dissociate Identity Disorder, which is also more commonly known as Multiple Personality Disorder. “Many people get Schizophrenia and Personality Disorder confused, especially since movies and television shows tend to use the terms interchangeably. Schizophrenia is what is considered a “thought disorder”, which means that disturbances in the thought process drive the illness” (Frese, 2009, P. 1).

Save your time!
We can take care of your essay
  • Proper editing and formatting
  • Free revision, title page, and bibliography
  • Flexible prices and money-back guarantee
Place an order

DID on the other hand, is much more uncommon than Schizophrenia, and instead of it being a “thought disorder”, it’s an “identity disorder”. In some cases, a lot of people with DID, have memory loss and they can barely remember when their personality changes, and or flips. When looking at Schizophrenia, one also needs to understand the symptoms that are tied to this illness. There are positive and negative symptoms with Schizophrenia. Positive symptoms of Schizophrenia are the presence of appropriate behaviors such as “agitated behavior, hallucinations, delusions, disorganized thinking, and nonsensical speech” (NIH, 2019). Negative symptoms, on the other side of the coin, are the presence of inappropriate behaviors; so basically the opposite of positive symptoms. These inappropriate behaviors include, “flat, emotionless voices, blank faces, rigid, motionless bodies, and mutism” (NIH, 2019). With some cases too, Schizophrenia also leads to episodes of psychosis. “Psychosis has been generally considered to be a severe break in reality that may result in psychopathic behavior” (Anderson, 1999, P. 39). In relation to Schizophrenia, psychosis or psychotic disorders include one or more of the following symptoms: delusions, hallucinations, disorganized speech, and catatonic behavior with brief or continuous episodes. It is said that due to him having Schizophrenia, David Berkowitz, or “The Son of Sam”, suffered from a psychotic break, and that is what lead him to go on his killing spree.

Case Studies: The Son of Sam and Cosmo DiNardo

Two individuals, one from the past, and the other one from the present, whose stories are linked, are, as mentioned above, “The Son of Sam”, and another young serial killer who emerged in 2017, twenty-year-old, Cosmo DiNardo. Cosmo DiNardo was responsible for the brutal murder of four young men in Pennsylvania, he tried to burn their bodies in a pig roaster after he committed the rather vicious crime. Even before the killings, Cosmo displayed erratic and dangerous behaviors; especially to his loved ones and friends. “A Bucks County prosecutor said Mr. DiNardo was once diagnosed with Schizophrenia. Members of his family and a lawyer representing Mr. DiNardo declined requests for more information about his mental health. One longtime friend said Mr. DiNardo twice spent time in a mental institution” (Gabriel, Haag, Hurdle, 2017, P. 3). Cosmo DiNardo talked about wanting to murder and harm other human beings since the young age of 14. “He often bragged to friends about seeing people killed, and in a social media post, he posed, bare-chested and crazy eyed, aiming a revolver” (Gabriel, Haag, Hurdle, 2017, P. 1). DiNardo, like the Son of Sam, had one of the biggest and or one of the most common identifiers, especially to other people, of Schizophrenia, hallucinations. In contrast with David Berkowitz’s story, DiNardo had visions of murdering other people and he proclaimed these to other people, as if he were getting a sign from God that he should be carrying out these atrocious acts. Like many other serial killers, many psychologists try to find logical reasoning as to why these haunted individuals murder innocents in cold blood. In a lot of documentaries about serial killers, criminologists like to make the argument that the killer had to have had something bad happen in their childhood in order for them to want to carry out terrible acts upon other people. However, when one truly thinks about it, this argument can be considered as faulty.

A lot of regular, everyday people have had terrible things occur when they were children, and they grew up to be fully functioning adults with no desire to harm others. If head injury or some other kind of trauma really was the cause of serial killers and their different methodologies, then hundreds of millions of serial killers would be roaming around the world wreaking havoc. “The consensus remains among experts that an unhappy childhood is not probable cause to commit murder and does not justify causation despite the infliction of abuse, genetic abnormalities, or brain trauma that one has suffered” (Anderson, 1999, P. 35). The article on DiNardo states that after an “ATV accident last year, DiNardo’s mood became especially dark. He was stranded for hours suffering from broken bones, until his father and younger brother found him. Some friends said he suffered a serious head injury” (Gabriel, Haag, Hurdle, 2017, P. 3). Sure, this accident could’ve caused DiNardo’s brain chemistry to flip, however in the article, there have been multiple reports that DiNardo has had multiple murderous fantasies since he was in the early stages of adolescence. His accident only happened when he was nineteen. Therefore, there really is only a miniscule correlation between DiNardo’s head injury, and his underlying mental illness.

After being arrested on a burglary charge, DiNardo also made a confession that he was responsible for the brutal killings of four young men who sought Mr. DiNardo out as their weed connection. “Prosecutors said that Mr. DiNardo lured the victims to a remote family farm in central Bucks County over two days, and along with Mr. Kratz (his cousin who was also his accomplice) shot them, ran one of them over with a backhoe and burned three of the bodies in a last ditch effort to cover their tracks” (Gabriel, Haag, Hurdle, 2017, P. 1). DiNardo had a psychotic break during his killings, he had multiple hallucinations of voices telling him to kill others, and he followed through. DiNardo had positive symptoms of Schizophrenia, even before his break, which was followed by appropriate behaviors. In relation to DiNardo, Son of Sam serial killer David Berkowitz “claimed to suffer from schizophrenia and blamed his killing spree on his neighbor’s dog who he also claimed was actually Satan, who then instructed him to {murder young women in the streets of Queens, New York}” (Frese, 2009, P.2).

Even though these men had Schizophrenia and they acted on their auditory hallucinations, it is extremely important to note that “individuals with a mental disorder were no more apt to commit a crime than those were not afflicted with Schizophrenia or acute psychotic disorders” (Anderson, 1999, P. 40). Just because people have Schizophrenia or any other type of mental illness, doesn’t mean they’re automatically destined to kill others.

Antisocial Personality Disorder and Psychopathy in Serial Killers

Another mental illness that will be briefly touched upon that is also extremely popular when diagnosing serial killers, is Antisocial Personality Disorder. Like the confusion between Schizophrenia and DID, there is also equal mix-up when it comes to Antisocial Personality Disorder and psychopathy. Psychopathy is not a clinical diagnosis, but it is considered a developmental disorder by different neuroscientists. “Many individuals with APD are not psychopathic, but a number of them, especially the ones who exhibit traits such as limited empathy and grandiosity, do demonstrate psychopathy. Psychopathic traits such as charm, manipulation, and intimidation have been recognized by the FBI as being thoroughly connected to serial murder” (Pemment, 2013, P. 1). People who are diagnosed with Antisocial Personality Disorder show no guilt or remorse when it comes to the law or receiving some sort of punishment. This is one of the reasons why serial killers are so commonly diagnosed with it.

When interviewing a serial killer, one commonly finds that they do not regret their actions or feel any guilt or remorse when they murdered their victim. They did it just to simply do it and they have no thought or need to take any of it back. “Antisocial behavior may also include stealing, drug/alcohol abuse, and disregard for authorities, killing/and or mutilating small animals, and setting fires. In adult serial killers it has been observed that they have a difficult time forming sustainable relationships” (Anderson, 1999, P. 41). An example of an individual who had Antisocial Personality Disorder, was Ted Bundy. He was responsible for the deaths of over 40 women during the 1970’s. Although he did meet the criteria for other mental illnesses, such as Narcissistic Personality Disorder and voyeurism, his diagnosis primarily fell in the APD category. When confessing to his crimes, Bundy often said that he felt nothing for his victims and that they simply existed and were in his range of sight. He didn’t have any sort of personal relationship with him, he just wanted to exercise his power over them, which is the NPD part of diagnosis. People with Antisocial Personality Disorder often “violate the rights of others” (Cromer, 2019), as well.

When Ted Bundy was arrested the first time in Florida, he took it upon himself to escape shortly afterwards; not even thinking about the repercussions for his actions. Just as mentioned previously, it is crucial to announce that not all people with Antisocial Personality Disorder are prone to becoming serial killers, it is just only a select few that do.

Conclusion: Recognizing Symptoms and Providing Help

After acquainting myself with bipolar disorder essay examples and researches, I can further appreciate the complexity of mental health conditions. Just as Schizophrenia and Antisocial Personality Disorder are the most common diagnoses amongst serial killers. While some people, like Son of Sam, Cosmo DiNardo, and Ted Bundy act upon their disorders, there are an abundance of people in the world who have these illnesses and do not do anything with regards to harming others. It is so important to recognize the symptoms within other people, especially in loved ones, and attempt to give them the help they deserve.


  1. Anderson, W. R. (1999). Can Personality Disorders Be Used As Predictors of Serial Killers? Retrieved from St. Joseph’s College
  2. Cromer. (n.d.). Personality Disorders. Retrieved from St. Joseph’s College
  3. Frese, S. (2009, September 09). Schizophrenia and Personality Disorder. Retrieved from
  4. Gabriel, T., Haag, M., & Hurdle, J. (2017, July 17). Cosmo DiNardo Took a Dark Turn Before Bucks County Killings, Friends Say. Retrieved from
  5. Schizophrenia. (n.d.). Retrieved from
  6. What Would We Find Wrong in the Brain of a Serial Killer? (n.d.). Retrieved from
Make sure you submit a unique essay

Our writers will provide you with an essay sample written from scratch: any topic, any deadline, any instructions.

Cite this paper

The Correlation Of Serial Killers And Mental Illness. (2022, Jun 29). Edubirdie. Retrieved June 20, 2024, from
“The Correlation Of Serial Killers And Mental Illness.” Edubirdie, 29 Jun. 2022,
The Correlation Of Serial Killers And Mental Illness. [online]. Available at: <> [Accessed 20 Jun. 2024].
The Correlation Of Serial Killers And Mental Illness [Internet]. Edubirdie. 2022 Jun 29 [cited 2024 Jun 20]. Available from:

Join our 150k of happy users

  • Get original paper written according to your instructions
  • Save time for what matters most
Place an order

Fair Use Policy

EduBirdie considers academic integrity to be the essential part of the learning process and does not support any violation of the academic standards. Should you have any questions regarding our Fair Use Policy or become aware of any violations, please do not hesitate to contact us via

Check it out!
search Stuck on your essay?

We are here 24/7 to write your paper in as fast as 3 hours.