Forensic Psychiatry

Comprehensive Analysis

Complex Psychiatric and Medical Cases

Leonard Weiss, M.D.   (512) 646-0880  Austin, Texas  Forensic Psychiatry Contact Us About Your Case

At the Interface of Law, Psychiatry, and Medicine

Leonard J. Weiss, M.D. is Board-Certified in Medical Specialties of the Body, Brain, and Behavior Applied to Legal Questions

  • Psychiatry
  • Forensic Psychiatry
  • Addiction Psychiatry
  • Addiction Medicine
  • Internal Medicine
  • Clinical Nutrition Fellowship

Learn More about Dr. Weiss

Forensic Evaluation and Medical Specialization  

Dr. Weiss draws on specialization in distinct psychiatric concerns as well as the overlap between emotional, mental health, and other diseases of the body. He draws on excellent credentials in Psychiatry, Addiction Medicine, and Internal Medicine. His forensic practice focuses on one or more of these specialties. 

Dr. Weiss has been in medical practice as an internist for more than 35 years and Board-Certified in Forensic Psychiatry for more than 20 years. He has conducted thousands of psychiatric and medical assessments at some of the most respected institutions in medicine.

Objective Medical-Legal Findings Grounded in Rigorous Assessment and Medical Science

Proper diagnosis and treatment can be effective. However, if medical malpractice or negligence occurs, the results can be damaging. Dr. Weiss makes no assumptions. He considers all possibilities and renders an objective opinion. He is retained by both plaintiff and defense.

Medically Complex Cases: Psychiatry and Internal Medicine

Dr. Weiss is uniquely qualified to render knowledgeable and thoughtful medical-legal opinions by report and testimony. He applies perspective about complex cases that involve psychiatric conditions or allegations of disabling conditions. He is also qualified to address interacting medical and mental conditions.

Examples include co-morbid conditions such as diabetes and Bipolar Disorder, organ failure and drug addiction, Traumatic Stress and conditions worsened by stress, prescribed pain medication, alcoholism and untreated depression, COVID recovery and mental illness.  Malingering is always a consideration.

The background of an individual’s medical condition is often disregarded or missed by psychiatrists unfamiliar or insufficiently trained in physical and organic disciplines, resulting in wrong or missed diagnoses. 

  • Assessment – IME – Records
  • Report of Findings
  • Consultant as an Unretained Expert
  • Expert witness as a Disclosed Expert Witness
  • Testimony

Forensic Psychiatry and Addiction

Dr. Weiss’ Forensic practice does not always address addiction, but if it does, he is Board-Certified in Addiction Psychiatry and Addiction Medicine and has been treating substance abuse disorders for more than 3 decades. Some cases are complicated by a Substance Abuse Disorder or Process/Behavioral Addictions which can impact judgment and behavior.

Speaking with Dr. Weiss is the best way to find out if his background is relevant to a case.

Experience: A Physician’s Analysis of the Co-Existing Body, Brain and Behavior

Dr. Weiss’ Background

Psychiatry and Internal Medicine. Dr. Weiss began his medical career as an internist in Michigan treating diseases of the body for more than 10 years, when he turned his focus to a long-standing interesting in Psychiatry 30 years ago.

The relationship between elements of Psychiatry and Internal Medicine are a powerful and compelling focus of his medical practice.


In 1993, Dr. Weiss pursued his interest in Psychiatry and became Board-Certified by the American Board of Psychiatry and Neurology, with  complementary Board-Certification in Addiction Psychiatry the following year. Also in 1994, he became Board-Certified in Addiction Medicine (ASAM) to better serve those patients treated for substance abuse. In 2009 the physician in ASAM were required to transition to re-certify under the American Board of Addiction Medicine (ABAM) in which Dr. Weiss become a diplomate in 2009.

Judicial System: the Role of an Expert Witness in Forensic Psychiatry.  As a psychiatrist and internist, Dr. Weiss was sought from time to time to opine in a legal matter, which has been the case for more than 2 decades.  Dr. Weiss has always been interested in the application of psychiatry/medicine to adjudicated matters. A portion of his time is now applied to Forensic Psychiatric cases, though his clinical practice remains his primary commitment.

Dr. Weiss was one of the first Psychiatrists to qualify for and achieve the American Board of Psychiatry and Neurology’s Board-Certification in Forensic Psychiatry in 1999.  

Nutrition. Dr. Weiss has a career-long interest in nutrition and completed a Fellowship in Clinical Nutrition at Memorial Sloan-Kettering/Cornell some decades ago while a practicing internist. Before that, he minored in Nutrition at MIT and did bench nutritional research there as well as in Medical School. After his Fellowship he sat for and passed the written and oral Boards for the American Board of Nutrition. Diseases (both psychiatric and physical), mood, efficacy of medications may all be impacted by diet, malnourishment (inadequate nourishment), sugar intake, and even the use and misuse of “dietary supplements.” In medical-legal matters, this training is relevant if the case includes one or more of these factors.

Academic Appointments

In addition to patient care, Dr. Weiss has served on the faculties of renowned Rush University Hospital/Rush Medical College and Michael Reese Hospital in Chicago, and Texas A&M Health & Science University in Austin.

Clinical Background

Dr. Weiss has treated patients in private practice in Chicago, Detroit, and Atlanta. In 2013 he opened Psychiatry Austin in Austin, Texas, where he has an active clinical practice.

MIT to Medicine.  Dr. Weiss received his medical training after achieving a degree in Mathematics at MIT. It became apparent to him that he found medicine to be the more interesting field though his mathematics background underscores Dr. Weiss’ interests in evaluating research and statistical medical findings of other Experts in medicine.

Dr. Weiss’ Medical Specialties Explained

Internal Medicine
Internal Medicine is the treatment of medical conditions including 
diseases affecting the heart, blood, kidneys, joints, digestive systems, respiratory symptoms, vascular systems, substance abuse, mental health”

American Board of Internal Medicine, ABIM (adaptation)

Psychiatry“Psychiatry is the branch of medicine focused on the diagnosis, treatment and prevention of mental, emotional and behavioral disorders…A psychiatrist is a medical doctor (an M.D. or D.O.) who specializes in mental health, including substance use disorders. Psychiatrists are qualified to assess both the mental and physical aspects of psychological problems. American Psychiatric Association (APA).

What is Addiction Medicine? Addiction Psychiatry?
“Addiction Psychiatry is a subspecialty that involves focusing on evaluation and treatment of individuals with alcohol, drug, or other substance-related disorders, and of individuals with dual diagnosis of substance-related and other psychiatric disorders.”  American Board of Psychiatry and Neurology ABPN

Addiction Medicine. The addiction medicine physician provides medical care within the bio-psycho-social framework for persons with addiction, for the individual with substance-related health conditions, for persons who manifest unhealthy substance use, and for family members whose health and functioning are affected by another’s substance use or addiction.  American Board of Addiction Medicine (ABAM)

“Your review…was an enormous help. Thank you for all your hard work.”

David J. Tuckfield, Esq.

The AL Law Group

Sample Clients

  • Private attorneys (please ask for references)
  • Texas Medical Board
  • Texas Physician Health Program
  • Professional Recovery Network
  • Texas State Board of Pharmacy (TSBP)
  • Texas State Board of Dental Examiners (TSBDE)
  • Texas Board of Veterinary Medical Examiners (TBVME), and the
  • Texas Optometry Board (TOB)


Medical-Legal Assessment

Consulting to attorneys about psychiatric and medical factors relevant to a case; conducting evaluations as a disclosed Expert Witness or undisclosed medical-legal consultant.

Independent Medical Examination (IME) of a party to the action, face to face, or by video. Collateral Interviews of relevant informants such as family members, medical staff, co-workers, depending on the case.

Medical-Legal Findings

  • Affidavits and Declarations
  • Written or verbal reports
  • Testimony

Reviewing Medical and Legal Records

Reviewing records sounds mundane but it is not. Records can contain valuable information and clues about a person’s health and mental state. Legal Records reveal still more about the “story” painted by the examinee and others.

Records Dr. Weiss routinely reviews:

  • Psychiatric
  • Treatment and diagnostic notes
  • Hospital, physician, specialists
  • Labs, radiology (MRI, CT), toxicology. As a Board-Certified Internist and Addiction Medicine specialist, Dr. Weiss is uniquely qualified to interpret these records
  • Depositions
  • Reports by Experts

Areas of Concentration

Psychiatric Disorders | Addiction | Internal Medicine | Complex Medical Interactions

Civil Litigation

  • Medical Malpractice | Standard of Care | Hospitals and Rehab
  • Brain Injuries (TBI) | Brain Diseases (Dementia, Alzheimer’s)
  • Addiction
  • Psychiatric Disability
  • Testamentary Capacity | Competency to Enter into a Contract
  • Competency and Incompetency
  • Geriatric Psychiatry | Dementia | Diseases of the Elderly

Criminal Cases

  • Criminal Responsibility
  • Fraud: Elder Abuse, Undue Influence
  • Psychiatric factors in behavior
  • Malingering
  • DUI/DWI 
  • Competency to stand trial
American Society of Addiction Medicine
American Board of Psychiatry and Neurology
American Academy of Psychiatry and the Law