The air was cool and damp. The frost-coated lawn pulsed red and blue. As Slidell and I crossed it, my insides felt like a lump of granite.
Larabee stood in the space between the Hyundai and the garage wall. Beside him was Joe Hawkins, an investigator with the MCME. On the floor between them was the metal death scene kit. Hawkins was shooting pics.
The driver’s door was open. Through it I could see Ajax slumped over the wheel, head twisted to the side, nasal mucus and saliva crusted on one cheek. His hands hung limp at his knees. A pair of tortoiseshell glasses lay on a mat by his feet. The macabre tableau brightened every time Hawkins’s flash went off.
“Doc.” Slidell’s way of announcing our arrival.
Larabee turned, thermometer in one gloved hand. Hawkins kept snapping away. “Detective Slidell. Dr. Brennan. Gotta love a brisk winter dawn.”
“What have we got?” Slidell opened his spiral.
“Probable carbon monoxide poisoning.”
“The guy offed himself?”
“The first responders found no signs of forced entry in the house or garage. No note. I’m seeing minimal trauma.”
“Minimal?”
“Abrasions on the forehead and right ear. Probably caused by the head impacting the wheel.”
“Probably?”
“Possibly.”
“Meaning suicide.”
“I’ll know after the autopsy.”
Most carbon monoxide deaths are due to accident or suicide. A few are due to foul play. Larabee knew and was being guarded.
“The garage door was down when Cauthern arrived?” Slidell asked.
“So I’m told.”
“The car hood wasn’t raised, right?”
“Right.”
“The vic have any grease on his hands?”
“No.”
Slidell scanned the small space where we stood. “No tools lying around.”
“I agree, Detective. This doesn’t look like an accident.”
“Time of death?”
“Based on body temp, I’d put it somewhere between twelve and two this morning. As usual, that’s only a rough estimate.”
“How long’s it take?”
“Death by carbon monoxide poisoning?”
Slidell nodded.
“Not long.”
Slidell frowned.
“It requires very little CO to produce lethal levels of carboxyhemoglobin in the body.”
The frown continued.
To his credit, Larabee showed no impatience. But he kept it simple. Very simple. “Carboxyhemoglobin disrupts oxygen supply to the cells.”
“Gimme a little more than that.”
“Okay.” Larabee did some editing. “Hemoglobin is a molecule found in the red blood cells. Its job is to circulate oxygen throughout the body. But hemoglobin has a strong affinity for carbon monoxide, CO. If both oxygen and carbon monoxide are present, hemoglobin is much more likely to bind with the CO. When that happens, you get carboxyhemoglobin, which can’t do the job.”
Larabee didn’t go into the fact that hemoglobin has four binding sites to maximize the capture of oxygen from arterial blood flowing from the lungs and to expedite its release into the tissues and organs. That in the presence of both oxygen and carbon monoxide, hemoglobin is two to three hundred times more likely to bind with the latter. That this binding with CO inhibits the release of O2 molecules found on the hemoglobin’s other binding sites. That, as a result, even if blood concentrations of oxygen rise, the O2 remains bound to the hemoglobin and isn’t delivered to the cells. That, as a consequence of oxygen deprivation, the heart goes into tachycardia, increasing the risk of angina, arrhythmia, and pulmonary edema. The brain short-circuits.
That carbon monoxide is very bad shit.
“We’re talking how much?” Slidell pressed.
“High blood levels of carboxyhemoglobin can result from air containing only small amounts of CO.”
“You breathe the stuff.”
“Yes.”