Diary of a Criminal Investigator-Chapter 299: Disappearing Drag Marks

"The Haizhou International Apartments are about 3 kilometers from the Bailan River bridge where Zhou Yang’s body was found."

"This apartment is also one of the three buildings we identified this morning as the possible site of a high fall."

"Combining that Zhou Yang lived here, we can basically determine that the location from which the deceased fell is this building."

Ren Qiang introduced the general situation currently in hand.

First, the identity of the deceased is confirmed, which is a very favorable condition for solving the case.

Second, the deceased’s residence can essentially be determined as the point of falling into the river.

Now, it’s necessary to follow the deceased’s network of relationships to determine whether the death was suicide or homicide.

"What has the Crime Scene Investigation team discovered?"

Liu Guodong shook his head, "Lu Chuan is conducting a final examination of the clothing worn by the body; it hasn’t been completed yet. Later, we also have to go to Haizhou International Apartments."

"Alright, everyone work hard to try to determine the nature of the deceased’s death today."

At the Crime Scene Investigation laboratory.

"Lu, how’s it going?"

After finishing the meeting, Liu Guodong called Sun Jun, who had already conducted a detailed inspection of Zhou Yang’s residence.

No special circumstances were found, and the neighbors were mostly tenants who did not know each other well.

However, since Zhou Yang rented a single apartment, the soundproofing was not very good, yet no strange noises were reported by the surrounding residents.

Based on Sun Jun’s investigation results, the possibility of Zhou Yang committing suicide by jumping is relatively high.

"Master, I found something."

Zhou Yang’s clothes have been checked, and Lu Chuan did not find any problems.

However, he checked the shoes carefully again, compared the unusual wear marks on the heels of both shoes by experimenting with his own shoes.

The conclusion was somewhat unexpected.

"Oh? What did you find?"

Lu Chuan picked up the shoes from the body and placed them under the spotlight.

"Here, the deceased’s shoes, about one-third of the pattern on the soles is worn, indicating the shoes are old and frequently worn by the deceased."

"And here," Lu Chuan placed the shoes flat, emphasizing the heel area: "The outer sides of the heels have wear marks similar to the forefoot."

"This indicates that the deceased tended to walk slightly pigeon-toed. I also contacted the forensic team, and from the leg shape of the deceased, we basically confirmed this judgment."

"But here, on the inner sides of the heels of both shoes, there are irregular relatively fresh wear marks."

"Wait a minute!"

Liu Guodong turned around, put on gloves, and took the leather shoes from Lu Chuan, observing carefully.

Indeed, on the inner sides of the heels, there are wear marks, and compared to the outer sides, the indentations are noticeably darker and have jagged edges.

All this indicates the marks must have been left in a short period of time.

"What do you mean?"

"The normal walking marks of the deceased mean that the inside of the heel shouldn’t have wear marks."

"I just conducted experiments with my own shoes, Master, look."

Liu Guodong put down the shoes and followed Lu Chuan to the side.

"Drag marks, when I dragged the shoes on the ground, similar marks were left."

The floor of the Crime Scene Investigation lab is cemented, without tiles, and Liu Guodong could clearly see a series of dark drag marks trailing.

The endpoint was a pair of leather shoes.

Liu Guodong picked up the shoes and saw almost identical marks to those on the inner sides of the heels of the deceased’s leather shoes.

"Homicide?!"

Lu Chuan nodded seriously.

"Most likely dragged before being thrown into the river, leaving marks due to the shoes rubbing against the ground."

"The possibility of homicide is very high!"

This discovery is crucial—a turning point in determining the nature of the case.

"Let’s go, Lu, come with me to Captain Qin’s office, and bring the shoes."

In Qin Yong’s office.

"I repeated the experiment in the basement, and we can basically confirm that the marks are from dragging."

Looking at the shoes in the evidence bag, Qin Yong carefully examined the fine marks on the inner heel sides.

"If these marks are indeed drag marks, then it can basically prove Zhou Yang was murdered and did not commit suicide."

A body can’t drag itself.

"Let’s check the crime scene. If there are drag marks on the shoes, there must also be drag marks on the ground!"

"Captain Qin, such drag marks are likely left on surfaces with high friction; it’s unlikely that Zhou Yang’s room has a cement floor, and floorboards or tiles wouldn’t leave such marks."

Lu Chuan added, "I suspect the suspect might have dragged Zhou Yang on the apartment roof."

"Don’t let Group Leader Sun’s people go up first; we might be able to collect the perpetrator’s footprints on the roof, don’t destroy it."

Qin Yong nodded, "Okay, I’ll make arrangements."

Forty minutes later.

Lu Chuan first entered Zhou Yang’s single apartment for investigation.

As imagined, Zhou Yang’s apartment was in complete disarray.

The coffee table was piled with leftover instant noodle boxes, takeout containers, cola bottles, and a bottle full of cigarette butts.

The place looked like it hadn’t been cleaned in a long time.

Lu Chuan focused on the floor.

The apartment had wooden flooring, untouched for an extended period, covered in a layer of grime.

But it was precisely this grime that allowed Lu Chuan to clearly determine if there were scrape marks.

As expected, the grime was intact, without any scrape marks.

There were also no signs on the windowsill of stepping or climbing, aligning with Sun Jun and his team’s results, ruling out the apartment as the crime scene.

"Let’s go upstairs."

After Qin Yong finished his call, Sun Jun’s team secured the apartment roof, and nobody had gone up since.

Lu Chuan put on shoe covers, gloves, and brought a transparent stepper but didn’t directly enter the roof.

The roof of Haizhou International Apartments was open, accessible through an aluminum door from the top-floor elevator machinery room.

This door was the only way to the roof.

So, Lu Chuan first collected fingerprints on the aluminum door.

If the perpetrator were a bit careless and didn’t wear gloves, he might have left fingerprints on the doorknob.

After doing this, Lu Chuan opened the door to the roof.

The rooftop was vast, appearing to be two to three hundred square meters.

The left side was a ventilation equipment area, and the right side was open space.

Lu Chuan cautiously moved with the transparent stepper, observing whether there were drag marks on the cement ground of the roof.

"How’s it going?"

Liu Guodong anxiously asked over the walkie-talkie.

"I haven’t found anything yet. Master, we have a portable variable-frequency spectrometer in the car; can you get it for me?"

"Sure."

The entire rooftop was visible at a glance, but Lu Chuan had already scanned it twice without finding any drag marks.

This didn’t make sense.

Zhou Yang’s leather shoes were black-soled. According to Lu Chuan’s lab experiments, dragged shoes would leave obvious black friction marks on the ground.

However, there was nothing on the rooftop.