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

"He handed over the evidence bag, which contained several cigarette butts. "We found them on the ridge of the field. They must have been left by the murderer. "

As dusk fell, the investigation continued. Yang Lin repeatedly photographed the lining of the deceased's clothes. Under infrared photography, the inside of the collar showed faint traces of sweat. Yang Sen packaged the extracted soil samples. Under the microscope, the metal debris mixed in the soil shone with a suspicious luster. Lu Chuan stood next to the tractor traces at the edge of the field, looking at the tire model made by the technician.

Lu Chuan's rubber soles rolled over the wet soil, making a slight "crunching" sound. Yang Lin half-knelt on the ground among the corn stalks, adjusting the lens of the Nikon D850 camera to macro mode, and the circular diffuser evenly spread the cold white light on the curled knuckles of the corpse. "Pay attention to this." He lowered his voice, and the tip of the tweezers was suspended above the blackened nails of the deceased. "There are light blue fibers embedded in the edge of the nail bed, which may be left by grabbing clothes during the struggle."

Yang Sen held a 20000D laser scanner, and the blue-green beams formed a flowing grid between the corn leaves. The scanner made a regular "beeping" sound, collecting 12 data points per second, and synchronously modeled the body shape, the direction of the dragging marks, and the surrounding environment. "The starting point of the dragging marks is 90 meters northwest." He pointed to the faint depression on the ground, "but the dragging track has three -degree turns, which means that the murderer adjusted the direction several times during the process."

Lu Chuan squatted down and shone a strong flashlight diagonally on the soil surface. Where the beam passed, fine gravel accumulated at the edge of the drag mark into an unnatural slope. "It's like a body is being dragged backwards." He marked key points on the ground with a red rope, "Take some soil samples to test whether there is human tissue." Yang Sen immediately took out a sterile shovel and collected three soil samples at the starting point, turning point and end point of the drag mark. The label on the sealed bag was wrinkled by dew.

Yang Lin began to examine the body in layers. He first put on anti-static gloves and used a soft brush to gently sweep the surface of the deceased's shirt at a 15-degree angle. Grayish-white dandruff fell into the black evidence plate, mixed with a few brown-red hairs. "The hair roots are intact and the hair follicles are clear." He put the hair into a transparent evidence tube, "It may belong to the murderer." When he lifted the collar covered with blood scabs, Yang Sen quickly used a multi-band light source to illuminate it, and a light purple fluorescence appeared in the depression of the clavicle - that was the residue of dried saliva.

"Blood splatter analysis." Yang Sen took out a protractor and a laser marker, and pasted fluorescent marking points all over the corn stalks. A numbered metal plate was inserted next to each bloodstain, like a miniature tombstone on the battlefield. He quickly tapped on his laptop, inputting the bloodstain height, angle, and area parameters. "The main splatter area is on the right rear side of the body, with an angle of 75 degrees, which is consistent with the murderer's movement trajectory of holding the weapon high and chopping down." Suddenly, he zoomed in on a stalk in the 17D model, "But there's a problem here - the bloodstain at the th mark spreads in a mist-like manner, indicating that the weapon lifted up soft tissue when it was swung."

Lu Chuan leaned over to check the straw, and there were tiny pieces of meat mixed in the dark red blood. "The murderer used a chopping weapon, and the blade was not sharp." He scraped a tissue sample with an evidence knife, "It might be a rusty sickle or axe." At this time, the rustling of corn leaves was accompanied by the sound of metal collision. Yang Lin found half a twisted button under the buttocks of the deceased. The resin surface was printed with a vague sailboat pattern. "It looks like it was on a work uniform." He put the button under a stereo microscope. In the 20x magnified image, the fine scratches were irregularly distributed, "It was formed by scratches from hard objects, maybe it was torn off during a fight."

In the halo of the survey light, Yang Sen squatted at the interruption of the drag mark. He gently pressed the soil with an electrostatic absorber, and the transparent tape immediately absorbed black debris. "Asphalt particles." He observed under the strong light, "The same material used to repair the road surface of the nearby county road." Suddenly, half of a broken shoe print was stuck on the edge of the absorber. Although only the heel part, the diamond-shaped anti-skid pattern was clearly visible. "About size 43, rubber material." He quickly took photos from multiple angles, "This kind of pattern is rare in the local market."

At dusk, Yang Lin began to photograph the shoe prints at the scene. He first sprinkled fingerprint powder around the shoe prints. Under the side light, the gray-brown soil surface gradually showed lines of varying depths. When the scale and direction indicator were in place, he took three sets of photos from directly above, at a 45-degree angle, and at a 90-degree angle. Each photo was precisely controlled for exposure compensation and white balance. "Pay attention to the wear on the heel." He pointed to the display screen. "The inside is severely worn, which means that this person is used to pronating his feet when walking."

Yang Sen focused on checking the body's belongings. There was nothing in the deceased's pocket except half a pack of damp cigarettes and a lighter. But in the back pocket of his jeans, he found a crumpled lottery ticket with a prize draw date three weeks ago. "Maybe we can find out the identity through the lottery sales point." He carefully unfolded the lottery ticket and suddenly noticed the oil stains on the edge, "Food oil stains, maybe fried chicken or dough sticks."

When the last set of physical evidence was labeled and put into a sealed box, the cornfield had completely sunk into darkness. On Yang Sen's 3D modeling screen, hundreds of data points flashed in the virtual crime scene, but he could never piece together a complete logical chain. "All the clues are too fragmented." He took off his protective mask, leaving a deep red mark on his forehead. "There are no biological samples, no identity tags, and even the murder weapon is just speculation."

Yang Lin wiped the lens and glanced at the investigation marks on the ground: "But the murderer left too many contradictions." He pointed to the broken corn stalks next to the drag marks, "He deliberately created drag marks, but left fingernail fibers on the body; he chose to dump the body during the autumn harvest season, but did not clean up the mud on the soles of his shoes. There must be breakthroughs hidden in these loopholes." The night wind swept across the cornfield, and the freshly broken corn piled on the edge of the field glowed coldly, and this silent battle with the murderer has just begun.

When Yang Liyao was doing the on-site investigation here, the body had already been transported back to the criminal investigation team, and the forensic doctor Zhang Kai from the detachment was performing an autopsy on the body.

The cold air from the autopsy room mixed with the pungent smell of formalin hit me in the face, familiar and disgusting.

Zhang Kai tightened the elastic band of the protective mask again, and the latex gloves collided with the stainless steel instrument tray with a crisp sound. The black body bag on the cart was slightly bulging, and the gas produced by decay was escaping from the zipper gap, with a sickening sweet smell.

"Begin recording." Zhang Kai coughed into the recorder and used a scalpel to precisely cut the zipper of the body bag. The deceased was lying on his side in a curled-up position, his face was dark green due to high levels of decay, and a large number of white maggots gathered around his lips. (End of this chapter)