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Postpartum Depression and Psychosis Expert Witness and Legal Consultant

Diana Lynn Barnes, Psy.D. LMFT PMH-C

Diana Lynn Barnes, Psy.D. LMFT PMH-C

13743 Riverside Drive
Sherman Oaks, California 91423

Phone(818) 887-1312


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Diana Lynn Barnes, Psy.D. LMFT is an internationally recognized expert on the assessment and treatment of perinatal mood disorders. She is a nationally known forensic expert in women's reproductive mental health and is available for both prosecution and defense on criminal cases involving postpartum psychosis, infanticide, pregnancy denial, neonaticide and child abuse.


Diana Lynn Barnes, Psy.D LMFT offers the following services: expert testimony, legal case consultation, document review, perinatal mood disorders assessment, psychotherapy, professional training and seminars, presentations for educational and public health events.

As the legal community becomes increasingly aware of the impact of a postpartum mood disorder on a new mother's state of mind with respect to her infant, the question of when to utilize the expertise of a woman's reproductive mental health specialist becomes particularly salient. There are a wide range of perinatal mood illnesses (those disorders relating to the period surrounding pregnancy and childbirth) that can affect a woman's behavior in relation to her baby.

Although postpartum psychosis, in which there is a dramatic break with reality, is the illness most closely associated with infanticide, severe maternal depression carries with it a high risk of impaired judgment, distortions in thinking, and emotional detachment that increases the potential for child neglect and abuse that can have criminal implications.

Clinical assessment of a mood disorder around child-bearing is complex because of the number of different ways in which these illnesses can present themselves with respect to symptoms.

Sometimes, as was the case with Andrea Yates, all of the children are put at risk by the harsh changes in mental health that occur with the birth of the last child; in other situations, only one of the children is targeted, and not necessarily the newborn, as in the case of a woman with psychosis who took the life of her middle child, a 2-year-old with special needs. However, it is the birth of the last child that becomes "the straw that broke the camel's back," particularly when a woman's health and even her sanity, has been repeatedly compromised by previous pregnancies and untreated depression.

The appointment of an expert specifically trained in woman's reproductive mental health is essential when fitting together the relevant pieces of a woman's reproductive and mental health history in order to determine whether there are any connections between her state of mind and the events surrounding the harm to her child. A clinician knowledgeable in the diagnosis and assessment of postpartum mood disorders is in the best position to ascertain whether the circumstances surrounding a particular case were driven by symptoms that would indicate a postpartum depression or psychosis.

Litigation Support Services

Diana Lynn Barnes, Psy.D LMFT, performs legal case review and consultation where perinatal mental health may be an issue. Also, she offers expert testimony as a nationally known forensic expert on postpartum psychosis, infanticide, neonaticide, and pregnancy denial.

Areas of Expertise


Diana Lynn Barnes, Psy.D. LMFT is a frequently interviewed consultant to the media as well as an international trainer and presenter on all facets of perinatal depression.

Dr. Barnes is the past president of Postpartum Support International (2002-2004) and currently sits on the Advisory Council for that organization. She is also on the training faculties of Maternal Mental Health Now in Los Angeles, 2020/Mom and Postpartum Support International. She has testified in Sacramento, California on legislation pertaining to perinatal depression and participated on the appeal process which led to the second trial of Andrea Yates. In 2006, she was appointed to the Maternal Mortality Review Panel, sponsored by California Public Health. She has written and spoken extensively on women's reproductive mental health in the legal arena. She is the editor and contributing author of the definitive text on Women's Reproductive Mental Health Across the Lifespan (Springer, 2014). She also authored the chapter on pregnancy denial and the chapter on Altruistic Filicide for the text "Infanticide and filicide: Foundations in maternal mental health forensics" (American Psychiatric Publishing, 2020). She is the 2009 recipient of a Lifetime Achievement Award presented by the Eli Lilly Foundation for her outstanding contributions to the field of maternal mental illness.

Diana Lynn Barnes maintains a private practice in the greater Los Angeles area specializing in women's reproductive mental health across the life cycle, pregnancy and postpartum-related mood disorders, infertility, pregnancy loss, and trauma.

Areas Served

Dr. Barnes accepts cases in all of the States and has been retained on state and federal cases including the following jurisdictions: Miami County, Florida; Milwaukee; Tulare County, California; Los Angeles County; Orange County; San Bernardino County; San Joaquin County; Oakland County, Michigan; Dallas/Fort Worth. , Pierce County, WA; Denver County, Colorado.

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Professional Experience

Psychotherapist specializing in women's reproductive mental health, particularly as relates to pregnancy and birth-related concerns and the onset of postpartum mood disorders for over 25 years. Extensive background on all facets of assessment and treatment of perinatal mood disorders. Widely published author, trainer and presenter, forensic expert on infanticide and neonaticide. Dr. Barnes has consulted with Henry Mayo Newhall Memorial Hospital in Valencia, California, to implement a comprehensive pregnancy and postpartum screening program, which she designed for the hospital. This "model" program brings together hospital, community and health care providers in a collaborative effort to identify women at risk for mood disorder during their pregnancies, treat them, and follow-up in the early postpartum months so as to eliminate symptoms and return them to functioning. In addition to clinical practice, Dr. Barnes teaches and lectures extensively in this field.


Licensed Psychotherapist, California

Legal Experience & Services

Diana Lynn Barnes has been retained on cases in jurisdictions including, but not limited to:

Los Angeles County (infanticide, neonaticide, pregnancy denial, child abuse, postpartum psychosis)
San Joaquin County, CA (pregnancy denial and neonaticide)
Kern County, CA (attempted infanticide, child abuse causing death)
Maricopa County, AZ (infanticide, postpartum psychosis)
Tulare County, CA (child abuse causing death)
Ventura County, CA (child abuse and termination of parental rights)
Pierce County, WA (postpartum psychosis and infanticide)
Oakland County, Michigan (infanticide)
Milwaukee, WI (infanticide)
Dade County, Florida (postpartum psychosis)
Dallas/Fort Worth (federal kidnapping)
Idaho, United States District Court (gender discrimination related to postpartum depression)
Miami County, Ohio (divorce and custody)
Orange County, CA (postpartum psychosis and infanticide)
Denver County, CO (pregnancy denial and neonaticide)


President of Postpartum Support International (2002-2004)
Postpartum Support International Advisory Council (2004-present)
Maternal Mental Health Now (2008- present)
20/20/Mom (national organization based in California)
Clinical member of the National Association of Psychosocial Obstetrics and Gynecology
Clinical Fellow of American Association of Marriage and Family Therapists
California Association of Marriage and Family Therapists


- Licensed marriage and family therapist / psychotherapist with extensive experience in the assessment and treatment of perinatal mood disorders and other aspects of women's reproductive mental health
- Widely recognized as a consultant and expert witness specializing in women's reproductive mental health on cases involving postpartum psychosis, infanticide, pregnancy denial, neonaticide and child abuse
- Also experienced in civil cases involving perinatal mood disorders as a legal concern. Published author, internationally known speaker, educator and advocate

Awards & Honors

2009 Lifetime Achievement Award presented by the Welcome Back Awards/Eli Lilly for "courage and achievement in the depression community."
Jane Honikman Award presented by Postpartum Support International for outstanding contributions in the field of maternal mental health and child-bearing (2007)

Seminars & Training

Dr. Barnes is a frequent keynote speaker and presenter at national conferences.

Among other training, she has spoken before the American Association of Marriage and Family Therapists, the California Association of Marriage and Family Therapists, the American Psychotherapy Association, La Leche League, the International Childbirth Education Association, Lamaze International, the International Association of Marriage and Family Therapists
She has also been a frequent presenter on postpartum psychosis and the law at the annual Prevent Child Abuse Texas conference as well as a regular keynote workshop presenter for the American Institute for the Advancement of Forensic Studies in Minneapolis. Dr. Barnes is a Certified PSI trainer on perinatal mood disorders.


Women's Reproductive Mental Health Across the Lifespan, ed. (Springer, 2014).
Infanticide and Filicide: Foundations in Maternal Mental Health Forensics (Chapter on Pregnancy Denial and Chapter on Altruistic Filicide) (APA, 2020)
Women's Mental Health and Reproductive Events During Young Adulthood In Women's Mental Health Across the Lifespan (chapter on Young Adulthood). (Rutledge, 2017).
The Journey to Parenthood: Myths, Reality and What Really Matters (Radcliffe, 2007).
Transition to Parenthood; A training manual for clinicians and childbirth educators (The Center for Postpartum Health, 2008).

She has also completed three home study courses on various facets of perinatal mood disorders for Western Schools. Her work has also been published in the Annals of the American Psychotherapy Association, the Psychotherapy Networker (a publication of the American Association of Marriage and Family Therapists); the Journal of Systemic Therapies, among many other academic and popular publications. She wrote the guidelines on the assessment and treatment of perinatal mood and anxiety disorders for the Perinatal Advisory Council of Los Angeles County.

With George Parnham, legal defense counsel for Andrea Yates, Dr. Barnes co-authored a position paper for Postpartum Support International entitled, "Perinatal Mood Disorders: The Legal Arena and Women's Reproductive Mental Health Specialist."

Professional References

George Parnham, JD, lead counsel, Andrea Yates trial
Margaret Spinelli, MD, author, "Infanticide."
Margaret Howard, Ph.D. Brown University, Clinical Associate Professor of Psychiatry and Human Behavior


Psy.D. Doctorate in Clinical Psychology - Ryokan College, Los Angeles, California
M.A. Marriage, Family and Child Counseling - Phillips Graduate Institute, Encino, California
B.A. Child Development - California State University Northridge, California

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