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

“Teacher Zhang, the deceased weighed 62.5 kilograms and his preliminary height was 175 centimeters.” Zhang Kai then gently rinsed the mud and weeds off the body with saline solution, being careful not to disturb any traces on the surface. During the rinsing process, he carefully observed the overall condition of the body: “The body is in a state of mild decomposition, rigor mortis has formed, mainly distributed on the jaw, neck, upper limbs, and large joints of the lower limbs. Lividity is located on the back, buttocks, and back of the limbs, and is dark purplish-red in color, which does not fade when pressed.”

"Teacher Zhang, based on the state of rigor mortis and livor mortis, can you make a preliminary judgment on the time of death?" Xiao Lin asked while taking notes of Zhang Kai's description. Zhang Kai pressed his fingers against the biceps of the corpse to feel the firmness of the rigor mortis: "Rigoletto has formed and spread to the major joints throughout the body, but it has not yet reached its most rigid state. The livor mortis does not fade when pressed. Combined with the mild degree of decomposition of the corpse, the preliminary estimate of the time of death is between 24 and 36 hours. However, the exact time needs to be further confirmed by considering the state of the internal organs and the degree of digestion of the stomach contents."

The physical examination officially began. Zhang Kai, holding a searchlight, started examining the body from head to toe. "The deceased is male, preliminarily estimated to be between 45 and 55 years old. His hair is black and white, about 3 centimeters long, with no obvious traces of hair dye. There are no obvious external injuries to the head, no depressed skull fractures, and no hematomas or lacerations on the scalp." He gently pressed on the deceased's head, examining it from the forehead to the back of the head. "The conjunctiva of the eyelids is congested, the cornea is slightly cloudy, the pupils are dilated, about 5 millimeters in diameter, and both pupils are equal in size and round."

“Could conjunctival congestion be a characteristic of death by suffocation?” Xiao Lin asked. Zhang Kai nodded and added, “Possibly, but we can’t draw a conclusion based on that alone. Many causes of death can lead to conjunctival congestion, such as sudden death or poisoning. We need to combine this with further internal organ examinations to confirm. Continue to examine other parts of the face.” Xiao Lin immediately used tweezers to gently open the deceased’s lips and examine the oral mucosa: “The oral mucosa is intact, with no damage, bleeding, or signs of corrosion. There are no loose or missing teeth, no bleeding gums, no bite marks on the tongue, and no foreign objects remaining in the mouth.”

The neck examination is a key part of the physical examination. Zhang Kai carefully palpated the deceased's neck with his fingers, checking from the thyroid cartilage to the supraclavicular fossa one by one: "There were no obvious ligature marks or strangulation marks on the neck skin, no subcutaneous bleeding, and no signs of fracture in the thyroid cartilage or hyoid bone." He asked Xiao Lin to measure the circumference of the neck with a tape measure: "The neck circumference is 38 centimeters. The skin elasticity is still good, and there are no obvious skin contusions or epidermal peeling." Subsequently, the two examined the deceased's upper limbs and found a superficial scratch on the back of the deceased's right hand, about 2 centimeters long and 0.1 centimeters deep, with irregular edges: "This scratch may have been formed during the struggle with the suspect, or it may have been caused by a sharp object when falling into the ditch. We will collect skin tissue from the scratch and surrounding secretions for analysis," Zhang Kai said.

During the examination of the lower limbs, the two investigators found that the soles of the deceased's black cloth shoes were covered with a large amount of mud, and there was a small amount of water inside the shoes; the socks were completely soaked. "The tread pattern on the soles is clear. Is there any possibility of it matching the footprints collected at the scene?" Xiao Lin asked. "We will send the sole tread pattern sample to the technical department for comparison with the footprints collected at the scene," Zhang Kai replied, while instructing Xiao Lin to separately package the deceased's shoes and socks, labeling them "External Surface Appendage Samples No. 1 and No. 2." The external examination lasted 40 minutes, during which six samples were collected, including skin tissue samples, oral secretion samples, and clothing fiber samples, and 156 photographs of the body surface were taken.

“No fatal external injuries were found during the external examination. The next step is an autopsy, focusing on ruling out damage, lesions, and signs of poisoning to internal organs.” Zhang Kai picked up a scalpel and made a standard “Y”-shaped incision in the chest and abdomen of the cadaver. The incision started on both sides of the shoulders, extending downwards to the xiphoid process of the sternum, and then down along the midline of the abdomen to above the pubic symphysis. The moment the scalpel cut through the skin, a small amount of putrefactive gas escaped, accompanied by a slight odor. Zhang Kai used tissue scissors to cut through the subcutaneous tissue and muscle, exposing the sternum and ribs: “The subcutaneous fat is about 2.5 centimeters thick, the muscle tissue is dark red, and there is no obvious bleeding or contusion.”

"Teacher Zhang, do we need to use a bone saw to open the sternum?" Xiaolin asked. "First, check for any rib fractures before deciding whether to fully open the sternum." Zhang Kai gently separated the soft tissue around the sternum with tweezers, pressing each rib with his fingers, checking them one by one from the first to the twelfth rib: "No rib fractures, no damage to the sternum, the thoracic cavity can be fully opened to expose the thoracic organs." Xiaolin immediately handed over the bone saw, and Zhang Kai started it, slowly sawing along the costal cartilage junctions on both sides of the sternum. The sound of the bone saw was particularly clear in the dissection room. A few minutes later, the sternum was successfully removed, and the thoracic organs were fully exposed.

"There is no blood or air accumulation in the pleural cavity, the pleura is smooth, and there are no adhesions." Zhang Kai carefully observed the internal environment of the pleural cavity, then used forceps to lift the heart and measure its size: "The heart is 13 cm long, 9 cm wide, and 6 cm thick, weighing 320 grams, which is consistent with the normal size of an adult male heart." He used a scalpel to cut open the ventricular wall and examine the condition of the myocardium: "The myocardium is dark red in color, uniform in texture, and there are no infarcts, bleeding points, or tumor lesions. There is no obvious stenosis in the coronary arteries, the lumen is patent, and there is no thrombus formation."

"How are the lungs? If it was death by suffocation, there should be corresponding changes in the lungs, right?" Xiaolin asked. Zhang Kai used tissue scissors to cut open the lung lobes and observe the color and texture of the lung tissue: "Both lungs are dark red, with a small amount of dark red blood oozing from the cut surface. The alveolar wall capillaries are dilated and congested, with blunt and rounded edges, and no obvious edema or consolidation. We will extract some lung tissue samples to test for the presence of drowning components and to check for changes in lung tissue caused by mechanical asphyxiation." He added, "Simply dilated and congested alveolar walls cannot determine whether it is asphyxiation; it could also be caused by blood pooling after death. We need to make a comprehensive judgment based on the condition of other organs."

After examining the thoracic organs, the two began examining the abdominal organs. Zhang Kai used tissue scissors to cut open the peritoneum inside the abdominal cavity, exposing the abdominal organs: "There was no blood or fluid accumulation in the abdominal cavity; the peritoneum was smooth and without adhesions. The liver was located in the right upper quadrant, measuring approximately 25 cm × 15 cm × 8 cm, weighing 1500 grams. Its surface was smooth, brownish-red in color, and without nodules, ruptures, or bleeding points." He used a scalpel to cut open the liver tissue to examine the lobular structure: "The lobular structure was clear, without fatty degeneration, cirrhosis, or tumor lesions. A sample of liver tissue was extracted for testing." (End of Chapter)