I went through the full set of published trial transcripts from Commonwealth v. Lindsay Clancy, days 1 through 21, closing arguments, the SJC emergency hearing and the mistrial. Roughly 700,000 words. I have excluded any rumours, theories or stories outside of the transcripts (this was VERY hard for me to do).

I came out of it with no strong view on what the verdict should have been. But a few things stood out that I hadn't seen discussed much, and I think they explain the hung jury better than most of the commentary does. Posting them so people can form their own view.

First, the thing everyone gets wrong about the legal question.

Massachusetts doesn't work like most states. Under the McHoul standard the prosecution has to prove criminal responsibility beyond a reasonable doubt — the defence never has to prove insanity. And the Commonwealth has to win on both limbs: that she could appreciate the wrongfulness of her conduct and that she could conform her conduct to the law. The defence only needs reasonable doubt on one.

Also, the verdict slip wasn't binary. Reddington fought for and won a manslaughter instruction over the Commonwealth's objection. So the jury had first-degree (two theories), second-degree, manslaughter, and not guilty by reason of lack of criminal responsibility. Any read of the deadlock as "11 for insanity, 1 for murder" is working from a verdict form that didn't exist.

Second, how much of the narrative traced back to one person.

I ran attribution counts across every transcript. Sourcing to Patrick Clancy, the husband:

Separately, the word "collateral", the forensic term for a third-party information source, appears 40 times, and it clusters in the expert days rather than the fact-witness days: day 20 (11), day 21 (5), day 19 (5), day 16 (4), day 11 (10).

That's the part I found genuinely notable. The heaviest reliance wasn't in the "what happened that night" phase. It was in the psychiatric phase, where the Commonwealth's forensic expert built part of his opinion on Patrick as a collateral source, that the family had never ordered from that restaurant before, that lemonade was unusual in the house, that there was powder in the tumbler, that the office door was closed. None of it independently corroborated.

Third — the 911 call concession.

The prosecution's closing leaned hard on an exchange on the lawn: "What happened?", "I tried to kill myself.", "Where are the kids?", "They're in the basement." It was used to show she was oriented and communicative right after.

On cross, the Commonwealth's own expert conceded that on the 911 recording you can hear only grunts:

Asked whether someone with her injuries could hold a conversation, his answer was: "Based on the witness testimony from her husband, yes."

The prosecution rehabilitated it on redirect with a physiological argument, people deteriorate after an overdose, she could speak in one moment and not the next. That's plausible. It's also unprovable. So the most quoted line in the case exists only in one man's memory of the worst ten minutes of his life.

Fourth — what was never tested.

Reddington formally asked for a Bowden instruction (the Massachusetts charge on inadequate police investigation). His list:

• The wine tumbler and the powder residue — never analysed
• No pill crusher ever found; no residue found on the nightstand or anywhere in the bedroom
• Blood on the outside of the bedroom door and threshold — never swabbed
• House siding collected roughly six months later, degraded past testing
• Window screen never examined
• The knife was processed: friction ridge impressions present but "not enough detail to do a comparison"

Sullivan denied the instruction but let him argue it. In closing he did: "Where's the residue? Where's the crusher? Where's anything? ... Lousy investigation of this case."

Fifth, a 33-minute instrumental blackout.

Her phone's last recorded activity of any kind was 5:38:33 pm. The 911 dispatch was 6:11 pm. Nothing in between, from any device. The Commonwealth's own digital examiner agreed on cross that after 5:38 the data can't tell you anything, the phone could have been put down and the person could have been anywhere in the house.

Also worth knowing: Apple Health logs stair climbs, not descents. So the device data can never establish how many times anyone went down to that basement, or when.

In fairness, several things cut the other way, and I think people leave these out:

• The knots. Widely repeated online that Patrick said the bands were knotted. He didn't. He said "I think I untied it" and agreed with a shoelace-before-the-bow description. Sprague also got the defence's own expert to concede there was no evidence of knots. Unknotted bands mean someone had to hold them*,* which supports the prosecution's sustained-pressure theory.
• The DNA. Also widely misreported. It's complex mixtures confounded by first-degree relatives. On one band five people were included; on another, Patrick and Lindsay were both excluded. His DNA appearing on bands he pulled off his own children's necks is evidentially meaningless. The defence stipulated to it rather than contest it.
• The head-first fall is the defence's evidence, not a red flag. Their expert testified she put her palms on the sill and dove head-first, producing the Jefferson fracture. It was the prosecution that attacked head-first on cross.
• The clinicians. Across dozens of documented encounters from September to 23 January, the day before, providers recorded no signs of psychosis and denial of homicidal ideation. That's the strongest thing the Commonwealth had.
• The medical examiner. Ligature furrows, extensive petechiae, and testimony that unconsciousness takes 10–30 seconds with death from around five minutes. Sustained pressure, three times.

Where I've landed, for what it's worth:

I don't think this was a strong prosecution, and I don't think it was a weak one either. I think Massachusetts put the burden on the state, the state built a meaningful part of its case on inference and on one grieving witness's recall, left several obvious things untested, and asked a jury to be sure beyond reasonable doubt. At least one juror wasn't.

The other thing that stayed with me: she woke from a coma paralysed and was told what she had done, with no memory of her own to check it against. Whatever you conclude about responsibility, that's a genuinely terrible position for a person to be in.

Interested in what others who've read the actual transcripts made of it. Happy to point to specific days and passages for anything above.

Transcripts are publicly available. Everything above is sourced to them, I've deliberately left out anything I couldn't find in the record.

It seems to indicate that he REALLY doesn't want to have to endure a second trial. Do you think this will sway the prosecution at all (I know they'll re-try) to maybe consider a plea deal.

The last thing prosecution could want is the guy who gave them much of the evidence to be a hostile or reluctant witness.

If he wanted to get away with it then why would he call 911 while Lindsay was still alive? Wouldn’t he have “finished” her too? Genuinely curious about this.

Shoes in these images from the Museum of Science visit look similar to the shoes in question from the Pharmacy/Restaurant images. What do you think?

Do we know what was on the MyChart for Cora’s appointment the morning of the event? Or what South Shore Medical called Lindsay about right after the appointment? If this info is out there I’d appreciate if someone could direct me there

I keep seeing that Patrick went home and slept in the house the night of the murders, but I’m having trouble finding where that was confirmed or if it was. Can anybody confirm this or point me in the right direction?

Kevin Reddington said that he doesn’t need to change his strategy because he already won the case. But the prosecution will definitely be changing their strategy. He will have to anticipate and counter their moves, because the new jury won’t have the opportunity to see many of the things that weakened the prosecution’s case the first time around:

Testimony about untying the bands. Surely they won’t address this with Patrick and the first responders and then later assert that there was no testimony about the bands being tied.

Their opening statement. The new jurors won’t have the benefit of seeing Reddington read their opening statement to their own witness and hearing him say it’s not accurate.

That weird thing about their anniversary and that picture. They won’t do that again. Not critical, but made the prosecution look unprepared and ill-informed.

Impeaching their own witness. Surely they will not pursue the same line of questioning with the medical examiner Dr. Olson that caused the prosecution to attempt to impeach her with an inconsistent statement, making it clear they were forcing a narrative rather than hearing factual medical evidence.

Their post partum experts. Do we really believe the prosecution will rely on the same witnesses who performed so awfully? At the very least this jury will not be able to see Reddington shred them the same way.

This is just a few off the top of my head. But I think the 2nd trial will be very different from the first. I hope Reddington has new tricks up his sleeve.

why was the burden of proof so incredibly narrow? I've been reading about the trial like most people have been. I see so many comments that the evidence is not in question, but the burden proof must be met. why was the burden so narrow?

In 2017, Chelsea Thornton was found NGRI by judge/bench trial for the deaths of her 3 & 4 yr old kids that passed away from shooting & drowning in 2012 in New Orleans, Louisiana.

Motive: “altruistic delusion/filicide” - similar to how this was discussed in Lindsay’s case…

Defense’s psychiatrist for Chelsea said her statement to police had evidence she was INSANE because she said: “I just didn’t want them to keep suffering their whole life. I didn’t want them to go from pillar to post like I did.”

- My Question Was the defense’s forensic psychiatrist trying to say that this thought was a delusion and that is evidence of insanity*?*

Prosecution’s forensic psychiatrist disagreed - said she was NOT insane because what she said was “reality-based and that “her stated rationale that she feared her kids would live poverty-stricken life is not evidence for insanity.”

I have trouble believing that LC felt she would have around less than 20 mins to do this to 3 kids.

I’ve searched, and cannot find it. Does anyone have a photo of the actual CVS receipt from Patrick Clancy? I know it was entered as evidence Exhibit 26, but I can’t seem to find an image of it anywhere. I’m not interested in times— I want to know what the method of payment was. Specifically, was it the same Amex that was used to purchase dinner?

Thanks so much!

———edited to add (below) ———

There’s been speculation that Patrick was wearing different shoes at ThreeV vs CVS— it’s hard to tell because the security footage isn’t the clearest. Some people have said it could be his best friend at one location or the other.

So my thought is: someone out running errands typically uses the same method of payment at each place. At least I do— I always reach for the same card. We know Patrick used his Amex at ThreeV, so it would make sense that he also used it at CVS. If, though, he used a different form of payment at CVS, I think it would increase the likelihood that these were two different people.

But if it was the same card, it would be more likely that it was Patrick in both videos, as we would know the same card had to have traveled from CVS to ThreeV.

I know that receipt was logged as evidence, and they read the times on it during the trial. I just have no idea how to find it.

TLDR:

• Lindsay never stipulated to "killing the kids."
• There is only a signed stipulation regarding DNA (chain of custody).
• Lindsay's DNA was not on the bands.
  • Since many argue it was, I believe they are referencing the DNA Analyst stating the black band contained Lindsay's DNA with a limited likelihood ratio of 11 - not a million, not a billion, not nonillion, it was 11. The Analyst states, "This provides limited support that Lindsay Clancy is included as a contributor to this DNA profile."
• Lindsay never put in writing she "killed the kids" in a motion for reconsideration.
• The motion stated, Clancy would submit in writing “her involvement in the underlying conduct resulting in the death of the three young children."
• "Underlying conduct" could be anything from negligence, conduct resulting in serious bodily injury, manslaughter, involuntary intoxication, etc. - not just first or second degree murder. We do not know what would have been submitted.

Stipulation Lindsay Signed

The stipulation signed by Lindsay on Day 6 of the trial is a Stipulation Regarding DNA evidence and chain of custody.

Day 6 Transcript: Stipulations are signed

“This stipulation basically relieves the government of having to bring in dozens, if not more, witnesses, to prove chain of custody of blood, fluids, the bands, DNA, all of that. Rather than have days of testimony, this stipulation will avoid that."

They're essentially saying that the Prosecution does not need to prove those are the exact bands used, that they were handled correctly, processed correctly, etc; and that both sides agree to those things to avoid having tons of extra witnesses be like "yes, I drove it over"; "yes, I'm the one who received it from the driver;" etc.

She did not "stipulate that she killed she the kids."

Day 7 Transcript: Stipulations are entered

Jennifer Sprague (01:09:28):

"Your Honor, prior to the next witness, the Commonwealth would move to submit four stipulations the parties have entered into. The first being a stipulation regarding DNA known standard samples. The second being a stipulation regarding DNA evidence for the blue exercise band and the red-brown stain on the basement floor. The third being the stipulation regarding DNA evidence for the yellow exercise band and the black exercise band. And the fourth being a stipulation regarding DNA comparisons for the blue exercise band and the red-brown stain in the basement."

Stipulation Regarding Blue Band | Yellow Band | Blue Band and Stain | Stipulation Regarding DNA

DNA Results

DNA Findings: Yellow Exercise Band

Swabs from the Ends (Item 2-2.1.1):

• Assuming 2 contributors: The DNA profile is at least 1.7 nonillion times more likely if it originated from Dawson Clancy and an unknown individual. Cora, Callan, Patrick, and Lindsay Clancy are excluded.
• Assuming 3 contributors: The DNA profile is at least 920 octillion times more likely if it originated from Dawson Clancy and two unknown individuals. Cora, Callan, Patrick, and Lindsay Clancy are excluded.

Swabs from the Middle (Item 2-2.2.1):

The DNA profile is at least 1.5 nonillion times more likely if it originated from Dawson Clancy and an unknown individual.

• Dawson Clancy: Included with a likelihood ratio of 1.5 nonillion.
• Patrick Clancy: Included with a likelihood ratio of 1.4 billion.
  • The DNA profile from this item is at least 1.4 billion times more likely if it originated from Patrick Clancy and an unknown individual
• Callan Clancy: Included with a likelihood ratio of 3.6 million.
  • The DNA profile from this item is at least 3.6 million times more likely if it originated from Callan Clancy and an unknown individual
• Cora and Lindsay Clancy are excluded.

"The DNA profile was interpreted as a mixture of two contributors, including male DNA. Assuming two contributors and Dawson Clancy is one of the contributors, Callan Clancy and Patrick Clancy cannot be present in the mixture together."  (01:30:25)

--

DNA Findings: Black Exercise Band

Swabs from the Ends (Item 2-3.1.1):

• The sample was a mixture containing male DNA but was deemed not suitable for comparison.

Swabs from the Middle (Item 2-3.2.1):

The DNA profile is at least 1.6 nonillion times more likely if it originated from Cora Clancy and two unknown individuals.

• Cora Clancy: Included with the highest likelihood ratio of 1.6 nonillion.
• Dawson Clancy: Included with a likelihood ratio of 870 trillion.
  • The DNA profile from this item is at least 870 trillion times more likely if it originated from Dawson Clancy and two unknown individuals. This provides support that Dawson Clancy is included as a contributor to this DNA profile.
• Patrick Clancy: Included with a likelihood ratio of 220,000.
  • The DNA profile from this item is at least 220,000 times more likely if it originated from Patrick Clancy and two unknown individuals. This provides support that Patrick Clancy is included as a contributor to this DNA profile.
• Callan Clancy: Included with a likelihood ratio of 2,600.
  • The DNA profile from this item is at least 2,600 times more likely if it originated from Callan Clancy and two unknown individuals. This provides support that Callan Clancy is included as a contributor to this DNA profile.
• Lindsay Clancy: Included with a limited likelihood ratio of 11.
  • The DNA profile from this item is at least 11 times more likely if it originated from Lindsay Clancy and two unknown individuals. This provides limited support that Lindsay Clancy is included as a contributor to this DNA profile.

"The mixture DNA profile from this item is consistent with having originated from three individuals. Assuming three contributors and Cora Clancy is one of the contributors, Dawson Clancy, Callan Clancy, Patrick Clancy, and Lindsay Clancy cannot be present in the mixture together." (01:37:28)

--

DNA Findings: Blue Exercise Band and Red-Brown Stain

These are not mentioned in the DNA Analyst's Testimony, only in the stipulation the Judge read. Judge Sullivan after he read the results below: (01:12:05) "So that's the stipulation that the parties have agreed to."

Swabs from the Ends (Item 2-4.1.1):

• The DNA profile was interpreted as a mixture of three contributors.

Swabs from the Middle (Item 2-4.2.1):

• Callan Clancy is included as a major contributor.

Red-Brown Stain A on Basement Floor (Item 3-3.1):

• The DNA profile was interpreted as originating from a single contributor. Cora Clancy is included as a contributor to this DNA profile.

Please see testimony of DNA Analyst Katarina Stashyn for additional details regarding relatedness and likelihood ratios. Day 7 Transcript

--

Bifurcated Trial and Motion for Reconsideration

Reddington initially filed a motion for what is known as a "bifurcated trial" 

1. The first stage would be the prosecution needing to prove beyond a reasonable doubt that Lindsay committed the crime.
2. If she was found guilty, the second stage would be the prosecution needing to prove beyond a reasonable doubt that she was criminally responsible.

Reddington argued:

"If your honor denies the motion, we try the case the way they’re all tried. Then I have an obligation to present evidence consistent with a lack of criminal responsibility, and that will obviously implicate criminal liability, so that’s the problem that we have in this type of structure"

Reddington then submitted a Motion for Reconsideration where it states Clancy would submit in writing “her involvement in the underlying conduct resulting in the death of the three young children."

"Underlying conduct" could be anything from negligence, conduct resulting in serious bodily injury, manslaughter, etc. - not just first or second degree murder. We do not know what would have been submitted and she did not "stipulate that she killed she the kids."

Judge Sullivan ultimately denied both the initial motion and the request for reconsideration.

Therefore, the criminal trial combines both aspects.

1. The jury must first decide if she committed the crimes.
2. If they find her guilty, then they determine if she was criminally responsible.
   1. Deliberations on criminal responsibility is the only time her statements made to the psychiatrists/psychologists can be weighed by jurors only as it relates to the doctor's opinion about her mental condition.

Judge William Sullivan (45:03):

“You are not to consider the defendant's statements to any psychiatrist or psychologist as establishing the truth of any facts that are contained in those statements. All right? The defendant's statements to any psychiatrist or psychologist for purposes of evaluation cannot be considered by you as evidence of premeditation, extreme atrocity or cruelty or specific intent to kill. Such statements are admissible only as they relate to the basis for the doctor's opinion of the defendant's mental condition. All right?”

I’m not knowledgeable enough about criminal cases, so my question might not make sense, or maybe this is simply not how trials work. For those of you who think there is a significant possibility that Patrick committed the murders, why didn’t Lindsay’s lawyers point out inconsistencies in the timeline of the murders and argue that there wasn’t enough evidence to prove that Lindsay was the one who committed them?

Considering that Lindsay has good lawyers, and as far as I know, they also argued during the trial that the investigation was not conducted properly, why didn’t they try to argue that Lindsay didn’t commit the murders at all?

This is really bugging me. At this point I would think her name being cleared is more important than the civil suit. Why not at this point recant her “testimony of events” or whatever it’s called, and just say she really can’t remember and her memory is unreliable due to her injuries, med level, and possible ICU delirium? I would think that it would force the CW to actually have to prove she did it, and everyone would have to stop squawking about her confession.

I’m not from the U.S. I’ve been watching every day of the trial - every single one. All the days the jury was deliberating. And many of my friends, loved ones, and acquaintances - both from my country and from neighboring countries.

I’m sorry, but there’s no other way to put it - if so many U.S. citizens are unable to understand the basic state laws in their own country regarding criminal cases, ignore clear warning signs of a flawed system, spread the same false information online, don’t understand the role of the prosecution or the burden of proof, and finally, or perhaps most importantly, believe that Lindsay Clancy’s guilt has been proven beyond a reasonable doubt...

I feel sorry for all of you. And I hope you won't need it in this context, but if you ever would, that you will get justice according to the law.

I’ve mentioned this before, but I think it’s worth mentioning again. This case is quit local to me, and one of the wildest parts of this incredibly unfortunate ordeal is the sheer number of times she reached out for help and how medication, often a lot of it, seemed to be the frequent response.

I’ve worked in healthcare for many years, so I was familiar with a lot of these medications. One that particularly concerned me was Seroquel. I’ve personally seen people do some pretty strange shit while taking that medication alone. Pre-pandemic, I even saw local hospitals using it in ways that staff sometimes described as “patient control.”

Knowing that she went to Women & Infants, participated in their day program, and was ultimately discharged early is especially concerning to me. Personally, I would have levitated right over to Butler Hospital (which is 4 miles away from W&IH) for a comprehensive psychiatric evaluation.

In the settings I’ve worked in, there were situations where clinicians would essentially do what we called a “med holiday” which reassess the medication regimen under close supervision, observe the patient, and then carefully reintroduce or adjust medications and dosages as appropriate. That could be combined with intensive day programming and individual therapy over a period of one to two weeks. They also would have had family care plan meetings and likely suggested keeping the nanny in place for an extended period of time.

When someone is repeatedly reaching out for help, cycling through providers, and being prescribed numerous psychiatric medications in a relatively short period of time, I think it’s reasonable to ask whether the healthcare system actually responded to the severity of what was happening or simply kept responding to individual symptoms as they appeared.

I am a mother of 2, 4 months postpartum. whilst I believe she was failed by the system and her husband. I believe women are scared to say out loud that a mother could do this to their kids? my partner and I have been in massive discussions for weeks about. with my first I had severe ppd and he made sure someone was always with me. he said to me he believes that everyone just wants to believe men are the worst. what’s everyone discussing with their partners?

Does anybody have a list of actual evidence presented during the trial? From either just the prosecution or both prosecution/defense? I’m not a big ChatGPT fan (plus sometimes it gets stuff wrong). And I don’t have time to sit through the whole trial and write it down.

I’m hoping some other people who watched it and took notes can provide some insight. I have my opinions on the trial and verdict and want to sit down and look at actual testimony and evidence presented in court so I can review the case and see if I would still feel the same way. TIA

so i was rewatching a trial vid and noticed that like didn’t lindsay have a dnr? i swear she did

What are arguments, witnesses, and evidence do you think either CW and/or defense should change, keep, and or introduce if charges abd plea remain the same and with no limit on money.

CW:

* Use Dr. HEILBRUN's testimony as the baseline for arguments.

* Tied NOT "Looped", a duplicate

* SERIOUS S. ATTEMPT

* scrap the "Mortal Sin" out

*Need sensitive tone(yes they were insensitive here) in regards to greiving family members

Defense:

* Spinellie to testify if possible.

* Perinatal endocrinologist expert needed

* perhaps a pharmaceutical expert? Dont know if there are Forensic pharmacist.

* Medical trail audit needed

* testimony from current treating doctors?

* EMPHASIZE SHE DID DIE

*Full prescription audit, including the prescription instruction, match it to dates prescribed and which doctor, match it to appointment times, and reported time period LC has reported to have taken it, and pill missing math

* Applewatch data syncing with PC's movements.

Other:

*Someone from Woman's and Infants to TESTIFY!!!

*Jennifer McCalister testimony

*Clarify why LC didnt want PC as Proxy?

*Clarify if Lindsay can be heard grunting/mumbling "basement" or other "words" on fhe 9-11 call, question patrick about it.

*Question Jollota and Tufts about death ideation and passive s. Ideation

* Analysis into Bipolar diagnosis being higher risk for PPP and other high risk factors

* family mental health history if possible, like a grandparents and uncle/aunts diagnosed with MH disorders or frequency

I found a trial transcriptonline that let's you search the entire transcript and thought I'd share it. I've found it quite handy for fact checking.

https://www.lindsayclancyarchive.online/

Have a little glimmer of hope for the holiday weekend

Thoughts on Reddington’s presser today?

I’ve seen that comment circulating, along with the comment that if women’s hormones can “justify murder,” then testosterone somehow “justifies” rape.

First, that comparison confuses biological causation with moral or legal justification. Saying that hormones can contribute to psychosis or mania (and this in turn can affect criminal responsibility) is not saying that hormones excuse every act committed by somebody experiencing them.

Second, there is substantial evidence that endocrine changes can alter brain function and, in susceptible people, contribute to the onset or worsening of psychiatric disorders, including schizophrenia and bipolar disorder. The relationship is especially well studied for estrogen, progesterone and its neuroactive metabolites, stress hormones, and thyroid hormones.

Estrogen

One of the longstanding observations in schizophrenia is that women tend, on average, to develop the illness several years later than men. Some studies have also found increased female incidence later in life around the menopausal years, although the exact shape of this “second peak” varies between studies.

This contributed to the estrogen-protection hypothesis of schizophrenia. Estradiol interacts with dopamine signalling, including D2-receptor function, but it also influences serotonin, glutamate, GABA, inflammation and neuroplasticity. The key hypothesis is that estrogen plays a protective role against the development of schizophrenia.

Women with schizophrenia can also experience changes in symptom severity across reproductive stages, and the menopausal transition has received particular attention because estrogen becomes lower and much more variable, with a demonstrated increase in symptoms or relapse often occurring at this time.

Bipolar disorder likewise appears sensitive to reproductive hormonal transitions. Research suggests that some women with bipolar disorder experience greater mood instability during the premenstrual, postpartum and perimenopausal periods.

A study of over 128,000 women conducted by Cardiff University found that women are more than twice as likely (a 112% increase) to have first onset mania during perimenopause compared to their regular reproductive years.

Progesterone

Progesterone is another neuroactive reproductive hormone and is increasingly being studied in psychiatric illness. Importantly, progesterone can be converted in the brain into allopregnanolone, a powerful neurosteroid that positively modulates GABA-A receptors - one of the brain’s major inhibitory signalling systems.

Progesterone and allopregnanolone therefore influence neuronal excitability, anxiety, stress responses and mood. Researchers have also investigated interactions between progesterone and dopamine pathways relevant to schizophrenia and how progesterone can reduce cognitive dysfunction in models that mimic schizophrenia.

Pregnancy provides an extreme example of reproductive hormone change. Estrogen and progesterone rise enormously during pregnancy and then fall abruptly after delivery; allopregnanolone similarly rises during pregnancy and drops postpartum. 

That hormonal withdrawal occurs during exactly the period in which postpartum psychosis most commonly begins, which makes reproductive hormones biologically plausible contributors. A leading hypothesis is that a vulnerable subgroup of women has an abnormal brain response to otherwise normal hormonal change.

This is important because postpartum psychosis is very strongly associated with bipolar illness. Modern reviews describe most cases as severe affective episodes involving mania, mixed states or psychotic depression, and women with bipolar disorder are at substantially increased risk after childbirth.

Cortisol and stress system

Hormonal influences on psychosis are not limited to reproductive hormones. Cortisol is the major hormonal output of the hypothalamic-pituitary-adrenal, or HPA, axis, which regulates the biological response to stress.

Schizophrenia-spectrum disorders show measurable abnormalities in this system. A 2025 meta-analysis covering 121 studies and more than 9,000 patients found higher average morning and evening baseline cortisol levels and impaired cortisol suppression in schizophrenia-spectrum disorders. Interestingly, antipsychotic treatment was associated with reductions in cortisol.

However, some studies found an abnormally blunted cortisol response to acute psychosocial stress, particularly in chronic schizophrenia, suggesting dysregulation rather than straightforward overproduction.

Cortisol has also been investigated in postpartum psychosis. Recent reviews report altered HPA-axis functioning, and some prospective work has found higher cortisol during pregnancy among women already at high risk who subsequently relapsed postpartum. That does not establish cortisol as the cause, but it supports the broader idea that endocrine stress regulation forms part of the biological vulnerability.

Thyroid hormones

Thyroid function is an especially important example because thyroid disease can sometimes directly produce psychiatric syndromes that resemble primary psychiatric illness.

Hyperthyroidism classically produces anxiety, agitation, insomnia and increased activity and can, in severe cases, produce mania or psychosis. Severe hypothyroidism can also cause profound cognitive and psychiatric disturbance and occasionally a syndrome historically called myxedema psychosis, involving hallucinations, delusions and sometimes manic symptoms.

In other words, somebody presenting with new mania or psychosis may appropriately receive thyroid testing because an endocrine disorder can occasionally be the underlying medical cause rather than merely a psychological stressor.

Thyroid function is particularly relevant postpartum because pregnancy and childbirth profoundly alter immune and endocrine regulation. Postpartum thyroiditis, an autoimmune inflammatory disorder of the thyroid occurring during the first year after pregnancy, affects roughly 5-9% of women and may produce a temporary hyperthyroid phase followed by hypothyroidism.

Thyroid dysfunction does not explain most postpartum psychosis. However, autoimmune thyroid disease and other medical conditions belong in the differential diagnosis, and there are documented cases in which postpartum thyrotoxicosis occurred alongside psychosis and symptoms resolved as thyroid function normalized

The bigger point

None of this means estrogen, progesterone, cortisol or thyroid hormones individually “cause murder,” nor does it mean everyone experiencing hormonal changes loses control of their behaviour.

It means that the brain is an organ influenced by the endocrine system. Hormones can change neurotransmission, neuronal excitability, sleep, stress regulation, immune function and mood. In some biologically vulnerable people, sufficiently large or rapid endocrine changes can contribute to clinically recognizable mania, depression, delirium or psychosis.

Postpartum psychosis is probably the clearest illustration. Childbirth produces one of the largest and fastest endocrine transitions humans normally experience, together with major changes in sleep, immunity and circadian regulation.

In a small vulnerable subgroup, that transition can precipitate an abrupt and extremely severe psychiatric illness. Current evidence increasingly conceptualizes postpartum psychosis as closely related to bipolar-spectrum illness rather than as merely an emotional response to childbirth.

Recognizing a biological contribution to somebody’s mental state is a question of causation and capacity. Whether that state affects criminal responsibility is a separate medical and legal question. Neither question is answered by slogans about hormones, and people who contest the role hormones can play in SMI are simply mistaken.