A young woman claims demons are speaking to her. A man insists evil spirits are controlling his thoughts. A teenager exhibits violent behavior and says she's possessed.

Are these genuine cases of demonic possession? Or are they psychiatric disorders that need medical treatment?

Dr. Richard Gallagher, a psychiatrist and professor who has spent 25 years evaluating potential possession cases, has a clear answer: You must rule out medical and psychiatric conditions first. Always.

This isn't optional. It's essential. And it requires rigorous scientific methodology.

Why Medical Evaluation Comes First

Dr. Gallagher is emphatic: "I always go into a case very skeptical. We do quite rigorous evaluations."

The reason is simple: Psychiatric disorders can mimic every single symptom people associate with demonic possession.

1. Hearing voices? Could be schizophrenia
2. Multiple personalities? Could be dissociative identity disorder
3. Violent behavior? Could be mania or psychosis
4. Claiming to be possessed? Could be delusion

If you skip medical evaluation and jump straight to spiritual solutions, you're:

1. Potentially harming someone who needs proper medical care
2. Allowing a treatable condition to worsen
3. Creating false possession cases that discredit real ones
4. Violating basic medical ethics

The Conditions That Must Be Ruled Out

1. Psychotic Disorders

What They Are: Conditions where people lose touch with reality, including:

1. Schizophrenia
2. Schizoaffective disorder
3. Brief psychotic disorder
4. Psychosis due to medical conditions

How They Mimic Possession:

1. Auditory hallucinations: Hearing voices that aren't there
2. Visual hallucinations: Seeing things others can't see
3. Delusions: Fixed false beliefs (like "demons control me")
4. Disorganized behavior: Acting bizarrely or aggressively
5. Paranoia: Feeling watched or persecuted

The Key Test: Dr. Gallagher notes: "I've dealt with thousands of these patients. They say 'I'm hallucinating and a demon is speaking to me.' You give them medication and the hallucination goes away."

If antipsychotic medication eliminates the "demon voices," it was a psychiatric condition, not possession.

2. Dissociative Identity Disorder (DID)

Formerly Called: Multiple Personality Disorder

What It Is: A condition where a person develops distinct personality states, often due to severe childhood trauma.

How It Mimics Possession:

1. Different "personalities" taking control
2. Memory gaps for what other personalities did
3. Dramatic personality changes
4. Different voices or mannerisms
5. Claiming to be different entities

Critical Distinction: DID personalities typically:

1. Have personal histories and backstories
2. Emerge gradually over time
3. Are connected to trauma
4. Don't display supernatural knowledge
5. Don't speak unknown languages
6. Don't have consistent hostility to religious objects

True possession:

1. Demon identifies itself as an evil entity
2. No personal backstory (it's not "Sarah from childhood")
3. Displays supernatural abilities
4. Shows extreme reaction to sacred objects
5. Has knowledge the person couldn't possess

3. Histrionic and Personality Disorders

What They Are: Conditions involving dramatic, attention-seeking behavior or deeply ingrained problematic personality patterns.

How They Mimic Possession:

1. Dramatic emotional displays
2. Attention-seeking behavior
3. Manipulation of others
4. Exaggerated symptoms
5. Self-harm or dangerous behavior

The Key Issue: Some people are manipulated into believing their destructive impulses mean they're possessed. Others consciously or unconsciously fake symptoms for attention.

Dr. Gallagher explains: "We see people who are histrionic or manipulated into believing that maybe their more destructive impulses mean that they're affected by a demon. I don't believe any of those individuals are possessed."

4. Sociopathy and Conduct Disorders

What They Are: Antisocial personality disorder, psychopathy, or severe conduct problems.

How They Mimic Possession:

1. Lack of empathy
2. Cruel or violent behavior
3. Manipulation and lying
4. Disregard for others' rights
5. Seemingly "evil" actions

Critical Point: Dr. Gallagher is clear: "Sociopaths have an evil side to them. I don't just assume that a sociopath is possessed. These are personality and character disorders, often with a lot of biological aspects."

Evil behavior doesn't equal demonic possession. Humans are perfectly capable of cruelty without demonic influence.

5. Bipolar Disorder (Mania)

What It Is: A mood disorder with extreme highs (mania) and lows (depression).

How Manic Episodes Mimic Possession:

1. Decreased need for sleep
2. Grandiose delusions ("I have special powers")
3. Rapid, pressured speech
4. Risky or aggressive behavior
5. Religious preoccupation
6. Extreme agitation and strength

The Distinction: Mania follows a pattern, responds to mood stabilizers, and doesn't include genuine supernatural phenomena.

6. Neurological Conditions

Conditions to Rule Out:

1. Temporal lobe epilepsy (can cause religious visions, déjà vu, altered states)
2. Brain tumors (can cause personality changes, hallucinations)
3. Encephalitis or brain infections
4. Dementia
5. Huntington's disease
6. Tourette syndrome (for involuntary vocalizations)

Why They Matter: Brain dysfunction can create bizarre symptoms that seem supernatural but have purely medical causes.

7. Medical Conditions

Physical Issues That Affect Behavior:

1. Thyroid disorders
2. Diabetes (blood sugar extremes affect mental state)
3. Autoimmune conditions
4. Infections affecting the brain
5. Medication side effects
6. Drug or alcohol intoxication/withdrawal
7. Sleep disorders (especially sleep paralysis)

8. Trauma and PTSD

What It Is: Post-traumatic stress disorder and complex trauma responses.

How It Mimics Possession:

1. Flashbacks and dissociation
2. Feeling "not in control"
3. Night terrors and nightmares
4. Hypervigilance
5. Emotional dysregulation
6. Feeling "invaded" or violated

Dr. Gallagher's Experience: "When I was at Cornell Medical College, I studied trauma formally. Literally hundreds of people who were traumatized. These people weren't getting demonically attacked."

However, he notes trauma can make people vulnerable: "Sometimes it can make them very bitter and unforgiving. And those are the kind of things - bitterness, cruelty, unforgiveness - that can sometimes open up people to the demonic."

The Rigorous Evaluation Process

Step 1: Complete Psychiatric History

1. Childhood development
2. Family psychiatric history
3. Previous diagnoses and treatments
4. Substance use history
5. Trauma history
6. Medical history
7. Current medications

Step 2: Mental Status Examination

1. Appearance and behavior
2. Speech patterns
3. Mood and affect
4. Thought process and content
5. Perceptual disturbances
6. Cognitive functioning
7. Insight and judgment

Step 3: Medical Workup

1. Physical examination
2. Blood tests (thyroid, glucose, etc.)
3. Brain imaging if indicated (MRI/CT)
4. EEG if seizures suspected
5. Toxicology screening
6. Other tests as needed

Step 4: Psychological Testing

1. Standardized assessments
2. Personality inventories
3. Cognitive testing
4. Projective tests if appropriate

Step 5: Trial of Treatment

For conditions like psychosis: "You give them medication and often the hallucination goes away."

If symptoms resolve with appropriate psychiatric treatment, the diagnosis was psychiatric, not demonic.

Step 6: Look for the Supernatural

Only after medical causes are ruled out, look for signs that cannot be explained by psychiatry:

1. Speaking fluent languages never learned (xenoglossy)
2. Accurate hidden knowledge
3. Supernatural strength beyond psychiatric agitation
4. Physical phenomena (levitation, objects moving)
5. Reactions to blessed objects the person doesn't know are blessed

What Psychiatrists Commonly See (That Isn't Possession)

Dr. Gallagher explains why psychiatrists tend to be skeptical:

"Psychiatrists are going to see people who say to them, 'I'm hallucinating and a demon is speaking to me.' You give them some medication and the hallucination goes away."

Psychiatrists see hundreds of cases of:

1. People claiming demons talk to them (auditory hallucinations)
2. People believing they're possessed (delusions)
3. People with alternate personalities (dissociation)
4. People blaming demons for their impulses (externalization)

What they rarely see:

1. Someone speaking fluent Bulgarian who never left their home state
2. Someone levitating for 30 minutes
3. Someone demonstrating hidden knowledge they couldn't possess
4. Genuine supernatural phenomena

This is why psychiatric evaluation is essential. Most claims of possession ARE psychiatric conditions.

The Combination That Indicates True Possession

Dr. Gallagher emphasizes: "A mentally ill person or medically ill person doesn't all of a sudden start speaking a foreign language they never knew. They don't have hidden knowledge."

What separates possession from mental illness:

Mental Illness Presents With:

1. Symptoms that fit diagnostic criteria
2. Response to appropriate medication
3. Explainable by brain dysfunction
4. Follows known patterns
5. No genuine supernatural phenomena

True Possession Presents With:

1. Multiple supernatural signs simultaneously
2. No response to psychiatric treatment
3. Phenomena that violate natural laws
4. Accurate hidden knowledge
5. Speaking unknown languages fluently
6. Reactions to hidden blessed objects
7. Manifestation of clear demonic entity

The key: It's the combination, not individual symptoms.

Red Flags That Suggest Mental Illness, Not Possession

1. Symptoms Started After Learning About Possession

If someone reads about possession, watches movies about it, then suddenly develops "symptoms," it's likely suggestion or attention-seeking.

2. Symptoms Resolve With Psychiatric Treatment

As noted, if medication eliminates the "demonic" voices or experiences, it was a psychiatric condition.

3. The "Demon" Has a Personal Backstory

Real demons identify as evil spirits. They don't claim to be "Sarah who died in 1892 and now lives in my head."

4. No Supernatural Knowledge or Abilities

If the person only has behavioral or experiential symptoms but displays no actual supernatural phenomena, suspect psychiatric causes.

5. Symptoms Match Psychiatric Patterns Perfectly

If everything fits neatly into schizophrenia, DID, or bipolar disorder criteria, that's probably what it is.

6. Person Has Clear Secondary Gains

If claiming possession gets them attention, excuses their behavior, or provides other benefits, be suspicious.

7. Cultural or Religious Hysteria

In certain communities or time periods, possession claims become trendy. The "Satanic Panic" of the 1980s-90s is an example.

The Psychiatrist's Role in Possession Cases

Dr. Gallagher describes his role: "I'm not an exorcist myself. I don't treat these individuals. I more or less just do assessments."

What the psychiatric consultant does:

1. Conducts thorough evaluation
2. Rules out medical and psychiatric causes
3. Looks for genuine supernatural signs
4. Provides documentation to church authorities
5. Offers ongoing consultation during treatment

What the psychiatrist does NOT do:

1. Perform exorcisms
2. Make final determinations (that's the church's role)
3. Treat with prayers or rituals
4. Skip medical evaluation

Why This Rigor Matters

1. Patient Safety

"I'm a physician and psychiatrist, but first of all, a physician. I went into this to help suffering people."

People need correct diagnosis and treatment. Treating schizophrenia as possession harms the patient. Treating possession as schizophrenia also fails.

2. Scientific Credibility

Rigorous evaluation makes the field credible. Sloppy assessment discredits genuine cases.

3. Ethical Responsibility

"I felt as a physician I shouldn't just say, 'You're too controversial a person for me to get involved.'"

Medical professionals have ethical obligations to suffering people, regardless of diagnosis.

4. Protection Against Fraud

Careful evaluation protects against:

1. Charlatans faking possession
2. Attention-seekers
3. Delusional individuals
4. Cultural hysteria

5. Clarity for All Parties

Church authorities, families, and the individuals themselves need clear answers about what they're dealing with.

The Church's Requirements

Dr. Gallagher notes: "At least in America and in a lot of countries, the leaders of the church, the bishops, they want someone to be rigorously evaluated."

Before authorizing an exorcism, the Catholic Church typically requires:

1. Complete psychiatric evaluation
2. Medical examination
3. Documentation of symptoms
4. Evidence of supernatural phenomena
5. Ruling out of natural explanations
6. Consultation with experts

This isn't bureaucracy. It's wisdom developed over centuries of dealing with these claims.

When Mental Illness and Demonic Influence Coexist

Here's where it gets complex: The two can coexist.

Someone with schizophrenia could also be demonically oppressed. Someone with trauma could also face spiritual attack.

Dr. Gallagher acknowledges: "Trauma can make people vulnerable psychologically, and they can turn to stuff. Sometimes it can make them very bitter and unforgiving."

The question becomes:

1. Which condition is primary?
2. What needs treatment first?
3. Are both factors present?

This requires even more careful discernment.

The Bottom Line: Skepticism Serves Truth

Dr. Gallagher's approach: "I always go into a case very skeptical. I'm not really skeptical anymore. I'm not a skeptic anymore. But I do believe they're rare."

The proper sequence:

1. Start skeptical
2. Conduct rigorous evaluation
3. Rule out all natural explanations
4. Look for genuine supernatural signs
5. Only then consider possession

Most cases will be psychiatric. That's expected and appropriate.

Some cases will be genuinely demonic. But you can only identify those by first eliminating everything else.

The priest who first approached Dr. Gallagher said it best: "I want someone skeptical. Then you're the perfect man for the job."

Skepticism isn't the enemy of spiritual truth. It's the protector of it.

When rigorous scientific evaluation is applied and a case still shows genuine supernatural phenomena that cannot be explained by any medical or psychiatric condition, then—and only then—can you seriously consider demonic possession.

The medical checklist isn't an obstacle to identifying true possession. It's the path to confirming it.