How Forensic Pathologists Differentiate Between An Accidental Overdose And A Suicide Overdose

Want to know how forensic pathologists differentiate between an accidental overdose and a suicidal overdose? Read our article to find out. 

Determining and classifying the cause and manner of death (accident, suicide, homicide, undetermined etc.. ) is important but can be particularly challenging where decease is associated with drug intoxication. Physical evidence found by police at the scene of death may provide some clues (e.g. a suicide note). Forensic pathologists can build up a likely sequence of events using analysis of toxicology reports, medical records and recent life events. 

If you’re interested in learning more about how forensic pathologists can distinguish between an accidental overdose and a suicidal overdose then this is the article you’re looking for. Carry on reading to look at some of the tools and techniques used by forensic pathologists to address this issue and run through some of the characteristics of accidental and suicidal overdose scenarios.

Establishing manner of death from drug overdose

Accurately determining cause and manner of death is important for mortality statistical surveillance as well as for informing public health research and policy. At the same time, it can potentially provide the family of the deceased with explanations or emotional closure after a traumatic event. Forensic pathologists are keen to establish the truth and have an array of tools and techniques to help them.

An accidental death is one where the fatal outcome was unintentional and there is little or no evidence that the drug was taken with any intent to cause harm or death.

In contrast, a suicide is a death which does occur through intentional actions to harm or kill oneself in taking the drug.

While there is no absolute rule or single easy formula for differentiating accidental and suicidal drug overdoses, there are certain characteristics and patterns which forensic pathologists can look for in toxicology reports. Combined with medical history and recent developments in the employment or wider life of the deceased, this can enable a forensic pathologist to make a good judgement on the likelihood of accidental death or suicide.

Where evidence from both the forensic pathologist and death scene investigation is insufficient to draw a conclusion, the manner of death may be classified as ‘could not be determined’ rather than accident or suicide.

This classification is intended solely for deaths where a thorough investigation is unable to establish a certain manner of death. It may be used where evidence for both suicide and accidental overdose are ambiguous or equally as strong / weak as each other after all available information has been taken on board and analysed.

Overdose deaths can occur with many prescription, non-prescription or illegal drugs but is most commonly found in misuse of opiates.

Why are drug intoxication deaths challenging for determining manner of death?

Determining manner of death in drug intoxication deaths can be particularly challenging for forensic pathologists for several reasons:

  • Evidence may be equivocal around factors including measured dose and intent to die.
  • Suicidal ideation and planning are commonly associated with opioid use disorders and suicidal intent by users may run on a continuous spectrum rather than being a yes/no determination.
  • Similar overlapping demographic groups are affected by both drug suicide and accidental overdose (e.g. middle-aged white men).
  • Similar overlapping risk factors exist for both suicide and accidental overdose (e.g mental health problems and history of drug abuse).
  • Social norms, religious beliefs, and conscious or unconscious beliefs and prejudices around suicide may influence behaviour among the family of the deceased or even the police and pathologists themselves. These kinds of attitudes may be behind underreporting of suicide from many causes.    
  • The number of drug intoxication deaths of all kinds has been rising in the USA and some other countries due to the ongoing opiate misuse epidemic.

In the USA the CDC publishes guidance for medical examiners and coroners on how to complete death certificates in drug toxicology deaths, including issues around manner of death.

Characteristics of accidental overdose

There appears to be no significant demographic difference between accidental overdose and suicidal overdose victims and both appear equally vulnerable to the majority of recent stressors, but there are other differences. Compared to suicidal drug deaths, accidental overdose victims may be more likely to:

  • display a chronic pattern of severe drug or alcohol abuse over time,
  • to have recently ceased or cut down their drug or alcohol intake for a time, potentially reducing their body’s tolerance to a substance and making them more vulnerable to overdose at levels which might once have been safe for them,
  • have experienced a previous episode of accidental drug overdose,
  • have been in recent conflict with an extended family member.

Characteristics of suicidal overdose

While individuals who die by suicidal drug overdose have similar demographic characteristics to those who die by accidental overdose there are some distinguishing factors. Compared to accidental and undetermined opiate drug deaths, suicides may be more likely to:

  • suffer severe depression, bipolar disorder and other significant mental health issues,
  • to have very high levels of a drug present in their bodies as documented in the toxicology report,
  • have attempted suicide on several previous occasions – this is one of the most reliable indicators of a suicide attempt,
  • have experienced a higher overall number of life-time stressors (e.g. divorce, unemployment, conflict bankruptcy etc..),
  • show higher levels of recent planning for death, including talking about suicide and writing suicide notes.

A final word… 

A forensic pathologist will work to integrate a range of relevant factors in coming to a view on whether a drug overdose death was accidental or due to suicide. Physical evidence from the scene (such as a suicide note) may be influential, along with toxicology reports, previous medical history and details of recent events and stressors in the life of the deceased.

Where evidence is incomplete or equivocal around suicide or accident, the forensic pathologist may advise that the manner of death cannot be determined.

We hope you’ve found this article useful and that it has given you some insights and food for thought on the work of forensic pathologists and how they can determine manner of death in drug overdose cases.

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