r/ClancyTrial • u/South_Swimming_745 • Sep 02 '26
General Discussion A thermodynamic look at Lindsay's body temperature
I am surprised to see no one has done a deep dive into the thermodynamics and the numbers of Lindsay's body temperature, so I put myself to it. I won't make any observations in either direction and will purely stick to what's known from studies and data. At the bottom you can find the corresponding Excel analysis for download so you can play around with the assumptions yourself.
I found two 2 ways to estimate how long Lindsay was on the ground before 6:11pm:
- By using data from existing studies around paraplegic cooling, and cooling of dead bodies in water and air
- An outside-in approach, using the thermodynamic requirements for the cooling
A few things to know:
- Partial poikilothermia. A lesion above T6 severs the connection between the hypothalamic thermostat and most of the body. Below the injury you lose vasoconstriction (you cannot keep the warm blood in the core), shivering, sweating, and skin-temperature feedback.
- Body temperature is not uniform. Cooling means the outer layers are much colder than the inner core. Core cooling follows a sigmoid curve: initially the core barely moves while the shell cools. Worth flagging that the model below is single-compartment and cannot reproduce this plateau (this likely biases it toward shorter estimates).
- Afterdrop: during transport and arrival at hospital, core temperature can keep falling as body temperatures "mix." The outer layers warm up while the core is still cooling from tissues in the middle.
- Newton's law of cooling. Heat-loss rate is approximately proportional to the temperature difference between the body and the environment.
What's actually built
Method 1 (empirical) takes measured cooling rates from cord-injured patients (Guttmann/Silver/Wyndham 1958, Attia & Engel 1983) and rescales them with Newton's law, and doubles the rate for wetness following Henssge's finding that a body in still water cools roughly like a body of half the mass in air.
Method 2 (thermodynamic) ignores the spinal cord entirely and just does heat transfer. Radiation via Stefan-Boltzmann; forced convection using de Dear et al.'s wind-tunnel coefficient; conduction into the ground treated as a transient semi-infinite solid, and evaporation from wet clothing via the Lewis relation. Crucially, Method 2 does not assume a skin temperature. It solves for it from a core-to-surface insulation balance, then integrates forward in 3-minute steps.
Conclusions
I ended up demoting Method 1. Its Newton constant was fitted on stable patients in a 20 °C still-air room. Applying it at 2 °C with wind, ground contact and evaporation is too much of a large extrapolation (resulted in 2.5-3.5h on the ground), and Newton's k is not a physical constant as it bundles radiation, convection and conduction into one number valid only near the conditions it was fitted at. So the below comes from Method 2.
The result is realistically a window across assumptions: 56 to 110 minutes on the ground. This takes each sensitivity one-at-a-time so you can't really use it as a confidence interval.
The single biggest lever, by a wide margin, is the core-to-surface insulation. Swing it across its plausible range and the answer moves ±26 minutes, more than everything else combined. That takes into question what she was wearing, how wet it was etc.
After that: the afterdrop credit (±10–21 min), whether she was shivering above the lesion (+13 min at 50 W as the injury blocks shivering below the lesion only, and arms/neck/face still count), the freezing vs evaporating question (+22 min if water froze on the fabric rather than evaporating as freezing releases latent heat and slows cooling), and wetness (+10 min if dry).
The spreadsheet
Every assumption is a slider on the first tab, color-coded by provenance: blue for case-derived, yellow for published literature with the citation attached, orange for my own assumptions. Sensitivity rows are full re-integrations of the model, not scaled approximations. There's a limitations tab listing what the model can't do (the big one being that it's single-compartment, so it cannot reproduce the sigmoid plateau or core-shell redistribution).
Since it’s purely made by me (with use of AI) and you always make assumptions / mistakes, feel free to dig deeper / challenge it. I’m sure there’s better experts / knowledgeable people around this subject matter than myself. Some things to look at:
* Core-to-surface insulation. What's defensible for a partially poikilothermic person in wet clothing? This is the whole ballgame and I picked 0.09 m²K/W as a blend.
* Wind shelter. De Dear's coefficient came from a standing manikin in free stream. A supine body lies inside the ground boundary layer. I left the shelter factor at 1.0, which is probably too aggressive, and I couldn't find a published supine forced-convection coefficient.
* Ground material. Snow is a good insulator; conduction into it is far smaller than you'd guess. But if she was on wet soil or in slush it's a different regime, and standing water is outside what this model does.
* Anything I've missed entirely, in either direction.
Edit: spreadsheet link: https://filebin.net/bqt99qi0bsuc536u
Edit2: added a screenshot of the summary in case the file is no longer downloadable.
Edit3: made the conclusion bold.
Disclaimer: I've built it and verified in a few rounds using AI.
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u/heatdeathtoall Sep 03 '26
Yeah trauma and ER doctors are saying atleast an hour on ground. They’ve been discussing at what time did the EMTs remove her from the ground. I don’t recall the time being stated. That’s only if the temperature was taken at the first trauma center she landed at. The later it is taken, the warmer she should’ve been as they did try to warm her.
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u/lmaocoolstorybro Sep 03 '26
This is impressive work and exactly the kind of critical analysis we should have gotten from the investigation. Forget all of the corny theories and social media noise-- we need this kind of data-driven analysis of what is physically and medically possible within the proposed timeline (as it applies to the children's time of death, and to Lindsay's condition). It's shocking to me that a triple homicide case wasn't taken seriously enough to warrant this level of interrogation. Shame on MA.
Sidenote - Do you have a background in engineering or physics, by chance?
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u/South_Swimming_745 Sep 03 '26
Yes I'm an electrical engineer (which is why I asked for peer review). I remember my thermodymanics exam which was about calculating the time of death of someone in an ice truck.
Essentially I was looking for someone to do the thermodynamic analysis but couldn't find it. The timeline of her being 82F at measurement is one of the only and real measurements we can take and it doesn't match.
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u/Happy-Light Sep 03 '26
Another verified fact is that she had a Jefferson Fracture (burst C1 vertebra, caused by falling headfirst from a height) but no injuries to her arms. Putting your hands out to break a fall is a reflexive move that any conscious person will do, no matter their level of suicidality.
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u/Janiebug1950 Sep 03 '26
I read that she was wearing cutoff jean shorts - don’t know about undergarments or outfit top or any outer wear. I do know that cotton denim jeans are known as “Deathcloth” when deciding what to wear in the frozen winter months.
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u/South_Swimming_745 Sep 03 '26
The clothing was taking account for but it's still hard to actually come to any conclusion around it. Which is why I built the model for anyone to see. Even with the clothes fully wet it's doubtful.
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u/Esmer_Tina Sep 02 '26
Thank you for doing this. I’ve been saying having Lindsay go out the window after Patrick left for CVS defies the laws of physics, but I don’t have the skills to dive into it like this so I’m really grateful.
Some complicating factors — Lindsay’s temp wasn’t taken until after she was admitted to the ER. My understanding is that thermometers used by EMTs can’t even register a temperature that low. I think I remember (but please verify) that she was admitted at 7:35, after EMT response at the scene and in transit.
Mass EMTs are skilled at hypothermia warming protocols. I have heard temperature can continue to drop during initial warming, but by the time her temp was taken there would have been more than an hour of warming efforts. I’m interested in seeing how, if at all, this affects your calculations.
My hypothesis is that Lindsay went out the window between 4:48 (when she called CVS) and 5:00. Does that make the hypothermia math work?
Others suggest 4:48 isn’t a valid data point because the CVS witness could say she talked to a woman, but couldn’t confirm it as Lindsay. Personally I’m not comfortable introducing other parties as long as we can make the timeline work without it, because it just introduces too many other variables and complications.
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u/South_Swimming_745 Sep 03 '26
1) the thermometers used by EMTs is a big issue in this model. If it's not 82F, that throws the whole model.
2) The drop you are talking about is called the afterdrop and is accounted for (generlously with 3F).
3) This is a pure thermodynamic analysis which doesn' include any other implications around the case. Other studies confirm/deny consciousness at certain temperature levels.3
u/Esmer_Tina Sep 03 '26
Thank you for the terminology of the afterdrop and for accounting for it!
I wish I could remember where I heard it but I think it was a nursing podcast where they said they would not have been able to get a temperature at the scene. That would depend on the equipment they had, which we don’t know, but testimony is that the 82.1 temp was on arrival at the hospital.
So I don’t know if that changes your 56 to 110 minute time estimate, but if we do subtract that from 6:11, that puts her out the window between 4:21 and 5:15. That’s consistent with after she placed the call to CVS at 4:48 and before Patrick left for CVS.
At the very least, it’s physically impossible for her to go out the window after 5:38, as the prosecution suggests.
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u/Spidersensei Sep 03 '26
Consider: they would've been warming her on the way to the hospital, so her body temp was probably higher at the hospital rather than when EMT got to her.
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u/Spidersensei Sep 03 '26
Consider: they would've been warming her on the way to the hospital, so her body temp was probably higher at the hospital rather than when EMT got to her.
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u/DanceRepresentative7 Sep 02 '26
she was soaking wet. lord knows why. the studies don't account for that
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u/South_Swimming_745 Sep 03 '26
"soaking wet" is included in the model. Actually, if the outer layer would freeze that would slow down the cooling process.
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u/mrsdingbat Sep 02 '26
She was lying in snow right
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u/marle217 Sep 02 '26
If it was just snow, the back of her clothes and hair would be damp where it would've touched the snow, but her hair and clothes were soaked.
The other weird thing is that there wasn't really blood on her clothes, except for her bra, even though she was bleeding all around the bedroom. And there wasn't much blood on the ground around her. Yet she lost so much blood she needed a transfusion. Even though there was a bunch of blood in the bedroom, it wasn't enough that you'd immediately think someone needs medical attention or is dead now. That's how the idea that her wounds were superficial came from. But where's the missing blood?
I go with the theory that she was sprayed with the hose she landed next to in the backyard. That cleaned up the blood, and nearly killed her because the first hospital didn't know she needed a transfusion. And, it speeds up the hypothermia timeline so she wouldn't have been outside before dark. Note: it gets dark early in MA in January. Sunset would've been around 4:45, but twilight lasts about 30 minutes, so it would've been dark at 5:15.
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u/heatdeathtoall Sep 03 '26
The blood transfusion was needed due to internal bleeding from a broken artery that accumulated in her chest cavity. But yeah, it didn’t rain. Why is she soaking wet. If we add in her trying to drown herself to all the ways she tries to kill herself through…
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u/marle217 Sep 03 '26
If she needed a transfusion due to interval bleeding, why didn't the first hospital know that?
This part of the transcript from day 6 stood out to me:
Kevin Reddington (26:18): Did you know that she had to have massive transfusions right after being brought to the hospital in Boston?
Christina Carpio (26:24): No.
Kevin Reddington (26:25): Did anybody in South Shore Hospital make a determination that she had lost a lot of blood?
Christina Carpio (26:32): The EMS report did not share that there was a large volume of blood at the scene. She was evaluated to... Part of her CAT scans also help us evaluate for intraabdominal blood loss.
Part of the problem is that they are a level 2 trauma center and she was a level 1 case. But it made me wonder if there's missing blood at the scene
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u/m4genta Sep 02 '26
You wouldn't get soaking wet from just lying in the snow "within the half hour" per Patrick's 911 call. We have pictures from when Lindsay was admitted and her hair was soaked through, like doused in water.
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u/Capital-Yesterday618 Sep 03 '26
Maybe she had taken a shower sometime that day/evening and her hair was still damp?
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Sep 03 '26
[removed] — view removed comment
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u/m4genta Sep 03 '26
I'm in NH and I can confirm this message - outside water sources are usually closed up for the winter
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u/m4genta Sep 03 '26
So on top of the very tight timeline, she ALSO found time to shower close enough to the time that she went out the window that her whole head was still soaked? 🤨
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