What is PTSD?

How PTSD is Evaluated in a Medico-Legal / Forensic Setting

By Sanjay Adhia, M.D.

What is PTSD?

PTSD, or Post-Traumatic Stress Disorder, is a psychiatric disorder that can occur in people who have experienced or witnessed a traumatic event such as violence, war, rape or serious accident. Prior generations associated PTSD primarily with military service and referred to PTSD as “shell shock” or “combat fatigue”. We now know that PTSD is by no means limited to battle.

Close to 7% of all people in the United States experience PTSD at some point in their life.

How is PTSD diagnosed?

Criteria for a Diagnosis of PTSD

A diagnosis of PTSD requires direct or indirect exposure to trauma. This is defined by the DSM-5 as “death, threatened death, actual or threatened serious injury, or actual or threatened sexual violence”. Some refer to this as the “gatekeeper” criterion.

Confusing Trauma with Other Stressors

Often, I will hear someone mention that a break-up or a job loss caused PTSD.

Although such stressors can affect someone with pre-existing PTSD, it usually does not get past the “gatekeeper” and qualify as a trauma.

In addition to the exposure to trauma, PTSD requires a certain number of symptoms under the following symptom clusters (abbreviated for this article.):

1) Intrusive Symptoms – nightmares, flashbacks
2) Persistent Avoidance of traumatic stimuli – either internally or as external reminders
3) Negative Alterations of mood or cognition – negative emotions or beliefs, decreased interest in pleasurable activities, decreased ability to experience positive emotions.
4) Alterations in arousal and reactivity – irritability, reckless behavior, insomnia, hypervigilance.

These symptoms must be present for over a month and cause significant distress or impairment. The symptoms cannot be due to medications, substances or other illness.

“Other Trauma and Stressor-Related Disorder”

This is a diagnostic category in the DSM5 which addresses psychiatric disorders which are not PTSD.

I recently examined an individual who met all the criteria for PTSD except for having no avoidant behaviors. I must consider other potential diagnoses such as Other Trauma and Stressor-Related Disorder, Acute Stress Disorder and Adjustment Disorders which, like Depression and Anxiety Disorders can be confused with PTSD.

Medico-Legal vs. Clinical Diagnosis

As a treating doctor, interviewing the patient and learning their own self-report of symptoms could be enough to initiate treatment. However, in a medico-legal setting, I prefer to obtain additional information.

Examples include collateral informants such as a family member’s observation of symptoms in a loved one. I also consider medical records, notes from a treating psychiatrist or psychologist, hospital or other records. Information about interpersonal and occupational functioning can be useful.

All of this information is helpful to establish or refute a diagnosis.

Diagnostic Criteria – Changes

It is worth noting there have been recent changes in the diagnosis in the DSM5 in contrast to the prior edition, the DSM IV. Some online sources reporting information about PTSD may be referring to outdated criteria. People are used to using the internet as a source of medical information but it can be dangerous or misleading if the information is outdated. The DSM5 is the current and most reliable information used by doctors in diagnosing PTSD. The DSM5 is not a reference for the layperson. I recommend conferring with a forensic psychiatrist if PTSD might be relevant in a legal matter.

Underdiagnosed and Over-diagnosed PTSD

As a clinician, I have seen PTSD go undiagnosed among patients who are instead diagnosed with Major Depressive Disorder and various Anxiety disorders. Evaluating diagnosis in isolation could lead to a misdiagnosis of PTSD. Stepping back and taking a larger view of all the symptoms, medical and psychosocial history, and subtler reports from the patient could improve diagnostic accuracy.

Diagnosis in Litigation

As a forensic psychiatric expert witness, I have seen PTSD over-diagnosed, meaning symptoms are diagnosed as PTSD which are better attributable to another psychiatric condition. Litigation following a traumatic event, such as a motor vehicle accident, can create an atmosphere in which symptoms are interpreted somewhat differently than, for example, a busy Veteran’s Administration (VA) psychiatry clinic. Additionally, it is my experience that the additional time necessary and available when I conduct a forensic evaluation enhances proper diagnosis (versus in a clinic.) The volume and type of data I require to help a treat a patient is different than what is required to inform a fact finder.

Disagreements Between Experts

An expert witness retained by opposing counsel may make a diagnosis different than mine, or arrive at a similar diagnosis but for different reasons.  

I take very seriously my responsibility to communicate to a jury or trier of fact the criteria and reasoning for any diagnosis made by a disclosed expert, including my own.  If I believe there are flaws in the opinions of another expert witness, the jury is best served by my explanation.  PTSD is complex and has a different prognosis and treatment than symptoms of other psychiatric conditions.

Damages are different for PTSD than other psychiatric disorders. PTSD is difficult to treat and medications target a range of symptoms (anti-psychotics, anti-anxiety medications and the like).  When Experts disagree about a PTSD diagnosis, it will impact a jury’s valuation of the case with consequences for Plaintiff and Defense.

What other diagnoses are seen with PTSD?

In many cases, I will see those with PTSD develop a Mood Disorder such as Major Depressive Disorder or an Anxiety Disorder. It is not rare for an individual with PTSD to develop Alcohol Use Disorder. In cases of a car accident causing PTSD, we could see a Traumatic Brain Injury. It is worth noting that TBI can share some, but not all, symptoms with PTSD.

What if my client (a litigant) does not meet criteria for PTSD but is severely affected by the trauma?

There are cases when someone is significantly affected by trauma but does not technically meet DSM5 criteria for PTSD. They could instead meet the criteria for “Other Specified Trauma/Stressor-Related Disorder,” which is not PTSD.

The person claiming to have PTSD is usually the Plaintiff, seeking recompense for their psychiatric damages. In a motor vehicle accident or traumatic experience shared by more than one party in a lawsuit, any or all could have symptoms of PTSD. One person might be diagnosed with PTSD while another is not. People vary in resilience and response to trauma.

A Forensic Psychiatrist does not assume PTSD is present despite what appear to be shared experiences between people and similar symptoms. Attorneys may want their own client to have an IME, or compel the opposing party’s IME. A defense attorney whose client experienced the same traumatic experience as Plaintiff might be tempted to obtain an IME for their client in the belief it will cast an alternate interpretation of damages. I recommend in such a situation that an attorney first retain a Consulting Forensic Psychiatrist for professional insight, before committing their client to an IME and a report by a disclosed Expert Witness on the legal record.

The Forensic Evaluation Does Not Presume Cause and Effect

The presence of PTSD, in of itself, is not necessarily psychiatric / emotional damage associated with the experiences at the heart of a particular lawsuit.

I may diagnose PTSD, but the timeline and events I discover in my assessment might indicate it was pre-existing. The presence of PTSD after a trauma does not imply either correlation or causation.

The Appropriate Psychiatrist

It is my opinion that any diagnosis of PTSD, or ruling out of a diagnosis of PTSD, requires the close review of a trained Forensic Psychiatrist. Medico-legal skill is different from that of a clinical psychiatrist without forensic training.

Consulting with a Forensic Psychiatrist: Worth Repeating

Attorneys should consider retaining a Forensic Psychiatrist as a consultant early in the case to advise about diagnoses and symptoms. This can help in evaluating the case and a client’s potential damages.  The benefits are so significant that I have addressed this option in “Consulting Expert: An Attorney’s Secret Weapon.”



1. The Diagnostic and Statistical Manual of Mental Disorders, 5th Ed. Is often referred to as the DSM-5.  Citation: American Psychiatric Association, DSM-5 Task Force. (2013). Diagnostic and statistical manual of mental disorders: DSM-5™ (5th ed.). Arlington, VA, US: American Psychiatric Publishing, Inc. http://dx.doi.org/10.1176/appi.books.9780890425596

2. Attorneys, litigants, even family members may be tempted to interpret symptoms using “common sense” or personal experience.  PTSD is complex. It can be masked by other conditions that are also self-diagnosed.  The DSM5 criteria for a diagnosis of PTSD likely is different from the “common sense” or general belief of what is PTSD. I suggest attorneys with their own impressions of their client as having PTSD or another psychiatric condition as an indication a Forensic Psychiatrist should be brought in to investigate further.


Posted 2019

Sanjay Adhia, M.D., Forensic Psychiatrist