Attending ex-girlfriend's wedding, arresting the groom's officer on the spot

“According to Henssge’s body temperature equation, combined with the body’s weight of 65kg and the heat dissipation coefficient of a single layer of clothing, this temperature difference corresponds to a time of death of 102-120 hours.” He suddenly pointed to the body’s armpit, where the hair was covered with tiny ice crystals. “The dew in the early morning will condense on the body’s surface, further lowering the surface temperature. This microenvironmental cooling effect will cause the core temperature to drop 15% slower than the formula calculates.”

Under multi-band light sources, the putrefactive venous network of the stomach wall reveals more complex layers. When illuminated by 450nm blue light, the network of blood vessels fluoresces red, resembling an abstract map. "Look at the density of these venous networks," Zhang Kai measured the spacing between adjacent vessels with a ruler, "averaging 0.3cm, densest along the midline of the abdomen, gradually thinning out towards the sides." He compared it with a standard atlas, "This distribution pattern only appears 72 hours after death. The low temperature of 18°C ​​slows down the formation of the venous network, but once formed, the color depth is clearer than in a high-temperature environment, which is why we can still see such a typical distribution after 5 days."

Xiaolin suddenly remembered something. She pulled out a photo of the deceased's fingernails. The lunula at the base of the nail had separated from the nail bed, forming a 1mm white gap. "The degree of nail bed separation is an important reference for the time of death," she pointed to the photo. "This width corresponds to 3 days of death at 20°C, but lower temperatures slow down the separation process. Converted to 18°C, the actual time of death should increase by 20%, which is about 3.6 days." She suddenly frowned. "But this data has a 6-hour error compared to the 102 hours calculated from the body temperature. How can we calibrate it?"

Zhang Kai's fingers tapped lightly on the dissection table, the rhythm resonating strangely with the clock on the wall. "Using a comprehensive scoring method," he picked up a pen and listed the indicators on a piece of paper, "Rigidity relief 3 points, corneal opacity 2 points, gallbladder fullness 4 points, venous network distribution 3 points, gastric contents digestion 3 points, plus a temperature correction factor of 0.85, the weighted total score is 15.5 points, corresponding to a time of death of 96-120 hours, or 4-5 days." He circled the final value, "The low temperature did delay decomposition, but the microenvironmental temperature of the body inside the van was 2°C higher than outdoors, and the sealed doors prevented heat from dissipating easily. This buffering effect offset some of the impact of the low temperature, so the final estimate is still in the 4-5 day range."

He had Xiaolin record all the calibration parameters, the pen scratching on the paper: "The most crucial thing is the digestive state of the stomach contents." He observed the meat fibers under the microscope again, "The striations are still clear, indicating that the degree of protein breakdown is limited. Combined with the intestinal environment of 18°C, the digestion speed is 50% slower than at a body temperature of 37°C. The digestion time that would normally be 4-6 hours will be maintained for a longer period of time in the low-temperature environment after death. This allows us to more accurately pinpoint the time window from eating to death, providing an anchor point for estimating the overall time of death."

As Xiaolin wrote the revised time of death, "8 PM on July 18th to 2 AM on July 19th," on the autopsy record, Zhang Kai was using a probe to pick up a strand of mesenteric fat. Under ultraviolet light, the fluorescence intensity of the fat was 10% weaker than that of the standard sample, direct evidence that low temperature slows down lipid oxidation. "This time range already takes the effect of temperature into account," he said, capping the autopsy record pen. The metallic clanging sound was particularly clear in the quiet autopsy room. "The next step is to match the parking lot surveillance timeline with this interval to see if that white Haval H6 was actually present on the night of July 18th."

The dissection continues.

“Considering multiple indicators,” Zhang Kai’s scalpel stopped at the heart, the rotting myocardium resembling boiled meat, but the subepicardial hemorrhages were still clearly visible, “the estimated time of death is between 8 pm and midnight on July 18th, based on: the degree of digestion of the stomach contents, the distribution of the putrefied venous network, the relief of rigor mortis, and correction to the ambient temperature of the parking lot.” He pointed to the fracture line in the right temporal region, “the cause of death is blunt force trauma to the brain, combined with traumatic shock. The skin defect on the neck was likely caused by post-mortem gnaws or dragging friction, and was not a fatal injury.”

The toxicology results arrived at 3 a.m. When Xiaolin rushed into the autopsy room with the report, Zhang Kai was stitching up the body. "No common toxins were detected in the blood," she said wearily, "but there were trace amounts of diesel fuel in the stomach contents, at a concentration of 0.8 μg/mL, possibly post-mortem contamination, consistent with the parking lot environment." Zhang Kai nodded, the rubber making a crisp sound as he removed his gloves: "Label all the samples clearly, especially the DNA from the fingernails and the fracture line parameters from the right temporal region. Compare them with the steel pipes from the scene tomorrow."

The lights in the autopsy room gradually softened in the morning light. Zhang Kai looked at the conclusions on the autopsy record; the judgments of the time of death and cause of death formed a complete logical chain between the lines. He knew that these professional analyses would provide crucial evidence for solving the case, and the old fracture of the deceased's right ring finger, the degree of digestion of the stomach contents, and the blunt force injury to the right temporal region would all become important clues in finding the truth.

While Zhang Kai was designing the autopsy, Zhang Hui was also comparing information on missing persons at the information center, as required by Lu Chuan.

Zhang Hui crumpled the packaging of his eighth cup of instant coffee into a ball and precisely tossed it into the trash can three meters away—he had repeated this action 27 times that night. The coffee stains in the trash can resembled an abstract painting, overlapping with the scrolling missing persons information on the screen. "The 837th one," he said, rubbing his aching neck, his knuckles tapping out a dull thud on the name "Zhang Jianjun." "35-year-old male, 178 cm tall, scar on the right temple... Oh, the scar isn't in the right place. The deceased's right temple was on the left temple."

Xiao Li, sitting next to him, suddenly let out a short laugh, then covered his mouth. His dark circles were thicker than his glasses lenses. He clicked the mouse haphazardly in the "reason for disappearance" section: "Brother Hui, is this system made with your feet?" He turned the screen to Zhang Hui. "Look at this 'Liu Zhiqiang,' the registered 'old fracture of the right ring finger' matches the deceased's characteristics, and the age of 38 also matches. But when you click 'details,' the photo is of a bald head, while the deceased clearly had hair!" He scratched his head in frustration, dandruff falling onto the keyboard. "What era is this? There are still photos from five years ago that haven't been updated."

Zhang Hui's fingertip hovered over the "Confirm Comparison" button, then suddenly stopped. "Check his social security records," he said, staring at the registered address on the screen. "He lived in the dormitory of the building materials factory in the west of the city, disappeared in 2021, and worked as a steelworker on a construction site before his disappearance." Xiao Li typed rapidly on the keyboard. (End of Chapter)