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

Meanwhile, the two also took panoramic photos and videos of the scene, created a scene investigation sketch, and marked key information such as the location of the taxi, the position of the deceased, the distribution of traces, and the location of physical evidence collection.

At 12:30 PM, Yang Lin and Yang Sen reported the investigation results to Lu Chuan: "Team Leader Lu, the preliminary on-site investigation is complete. The deceased has been identified as taxi driver Zhang Tiancheng, 45 years old, from Chengbei District. The on-site investigation revealed multiple fingerprint samples collected from inside and outside the taxi. Among them, an unfamiliar fingerprint was found on the steering wheel, gear lever, and handbrake, which is suspected to have been left by the suspect. A male footprint and several drops of blood were found around the taxi, which are suspected to be related to the suspect. The cigarette butts, invoices, and vehicle recorder memory card collected at the scene may contain important clues."

"What are the current points of doubt?" Lu Chuan asked. Yang Lin replied, "First, no murder weapon was found at the scene, so the specific cause of death cannot be determined; second, the correlation between the unfamiliar fingerprints and the suspected suspect's footprints and bloodstains has not yet been confirmed and requires further examination by the technical department; third, the vehicle's dashcam memory card needs data recovery to confirm the information of the last passenger the deceased picked up; fourth, there are slight scratches and blurry fingerprints on the trunk latch, which does not rule out the possibility that the suspect attempted to open the trunk, but the purpose is unclear."

Yang Sen added, "Furthermore, no obvious signs of a struggle were found at the scene. The victim's clothing was torn, suggesting that he was attacked without warning. The white synthetic fibers extracted are different from the cotton fibers in the victim's clothing and may have come from the suspect's clothing or the weapon used in the crime, but the source cannot be determined at present. Overall, we have not yet found any major clues pointing to the suspect, and the investigation still faces considerable difficulties."

After hearing the report, Lu Chuan immediately made arrangements: "First, the technical department should immediately conduct a comprehensive examination of the extracted physical evidence, focusing on comparing the fingerprints of the stranger with those of the deceased, and the correlation between the bloodstains at the scene and those of the deceased. We should also recover the data from the vehicle's dashcam memory card and analyze the composition of the white synthetic fibers. Second, we should arrange for investigators to conduct a comprehensive investigation into the social relationships and operational trajectory of the deceased, Zhang Tiancheng, and to visit his family, friends, and colleagues to find out if he had any enemies or debt disputes. Third, we should retrieve surveillance footage from the area surrounding the crime scene and along Zhang Tiancheng's operational route, focusing on suspicious individuals and vehicles between 11:30 p.m. the previous night and 5:00 a.m. on the day of the incident. Fourth, we should conduct DNA testing on the cigarette butts extracted from the scene in an attempt to identify the suspect."

Subsequently, the body of the deceased, Zhang Tiancheng, was transported back to the Criminal Investigation Detachment to await an autopsy to determine the specific cause and time of death. The crime scene remained cordoned off, and technical personnel were conducting a final review to ensure no trace or physical evidence was overlooked. Lu Chuan stood at the crime scene, staring at the green taxi before him, his brow furrowed. This early morning taxi driver murder case, like a mystery, perplexed every investigator. But Lu Chuan knew that the more complex the case, the more patience and meticulousness were required. He believed that as long as he persisted in focusing on the crime scene and relying on physical evidence, he would surely find a breakthrough and bring the suspect to justice.

Around 1 p.m., the hearse carrying Zhang Tiancheng's body smoothly drove into the courtyard of the Criminal Investigation Detachment's Forensic Identification Center. Forensic pathologist Zhang Kai, who had been waiting there, immediately led his assistant, Xiao Lin, to prepare for the autopsy. "Xiao Lin, first, collect basic information about the body before the external examination, recording the clothing, surface attachments, and general condition. Then, transfer the body to the autopsy table and prepare the instruments," Zhang Kai instructed Xiao Lin while putting on his dissection gown, gloves, and mask. Inside the autopsy room, the bright, focused light from the operating lights illuminated the stainless steel dissection table, where various dissection instruments were neatly arranged, including scalpels, tissue scissors, rib shears, skull saws, hemostatic forceps, tweezers, and measuring rulers, exuding a professional and solemn atmosphere.

Following Zhang Kai's instructions, Xiao Lin first collected basic information about Zhang Tiancheng's body: "Teacher Zhang, the deceased is a 45-year-old male, 175cm tall, weighing 70kg. He is fully clothed in a taxi driver's uniform. There are irregular dark stains on the chest of his shirt, which, based on preliminary observation, appear to be bloodstains, consistent with the scene investigation. There are no obvious external injuries on the body, and no obvious skin breaks, contusions, or fractures were found." Zhang Kai nodded, signaling Xiao Lin to continue: "Carefully examine the body surface for any attached substances, especially in areas such as hair and fingernails, and extract any remaining fibers, hair, or trace amounts of material."

Xiao Lin combed the deceased's hair with tweezers and extracted a hair sample using a fiber extractor, labeling it "External Sample No. 1". Then, she carefully pried open the deceased's hands and examined the fingernails with a magnifying glass: "Teacher Zhang, there is a small amount of grayish-white dust under the deceased's fingernails. No obvious bloodstains, hair, or fiber residue were found. A dust sample has been extracted with a cotton swab and labeled 'External Sample No. 2'." Zhang Kai added, "After sealing the extracted samples, we immediately sent them to the technical department for comparison with the hair and fiber samples extracted from the scene."

After collecting the basic information, Zhang Kai and Xiao Lin worked together to lift the body onto the autopsy table and begin the formal post-mortem examination. "Let's start with the head, focusing on checking the scalp for subcutaneous bleeding and skull fractures," Zhang Kai explained, gently parting the deceased's hair with a scalp scalp and examining each area of ​​the scalp. "The scalp is intact, no subcutaneous hematoma was felt, and there was no obvious indentation or bone friction in the skull, preliminarily ruling out the possibility of blunt force trauma to the head." Zhang Kai explained to Xiao Lin while examining the body, "The eye examination is crucial; in cases of asphyxiation, the eyes usually show characteristic changes."

Xiao Lin gently pulled open the deceased's eyelids with an eyelid retractor, and Zhang Kai carefully observed with a magnifying glass: "The cornea is slightly cloudy, the pupil is dilated, about 5mm in diameter, and there are scattered subconjunctival hemorrhages in both eyes, about the size of pinpoints, evenly distributed. This is one of the typical signs of death by asphyxiation." Xiao Lin asked doubtfully, "Professor Zhang, are subconjunctival hemorrhages always caused by asphyxiation? Could there be other causes?" Zhang Kai explained, "Subconjunctival hemorrhages form due to oxygen deficiency during asphyxiation, leading to increased permeability of small blood vessels and blood leakage. Of course, violent coughing and vomiting can also cause subconjunctival hemorrhage, but considering the deceased's overall condition and the lack of signs of struggle at the scene, asphyxiation is more likely. Further confirmation through autopsy is needed." (End of Chapter)