Suspect 037

Before long, Zhao Ming and the technical team arrived at the scene.

“Sorry for being late, Captain Zeng.” Zhao Ming scratched his head.

“What took you so long? Why did you get here so late?” Zeng Ping asked.

“I was playing live-action CS with some friends, and it was a bit far from here,” Zhao Ming replied.

“Well, you certainly keep your life colorful,” Zeng Ping laughed.

“I wanted to practice my shooting skills. It might come in handy when apprehending criminals,” Zhao Ming explained.

Zeng Ping didn’t dwell on it, instead turning to Lu Wen from the technical team, instructing him to collect fingerprints from the camera in the bathroom.

“Do you have any items belonging to your boyfriend?” Han Bin asked.

“There’s his water cup under the table,” Chen Luyan said, reaching out to take it.

“Don’t touch it. Let me,” Han Bin said. Wearing gloves, he retrieved the cup from under the table.

“There are fingerprints,” Han Bin announced, handing the cup to another member of the technical team to collect the prints.

“Captain Zeng, are there any fingerprints on the envelope or the USB drive?”

“No obvious fingerprints,” Zeng Ping replied.

A short while later, Lu Wen and another colleague from the technical team had gathered the fingerprints and used a portable police fingerprint comparison device to conduct on-site analysis.

This method allowed them to quickly determine investigative directions and shorten the time required to solve the case.

“Captain Zeng, the fingerprints on the camera and the cup aren’t from the same person,” Lu Wen reported.

Zeng Ping acknowledged this and handed the envelope and USB drive to Lu Wen. Some fingerprints aren’t visible to the naked eye but can be detected using chemical agents and specialized equipment.

Of course, if gloves were worn or the items wiped, no fingerprints would be left.

“Officer, does this mean my boyfriend can be cleared of suspicion?” Chen Luyan breathed a sigh of relief.

If her boyfriend had truly been responsible, she would have felt even more frightened.

Zeng Ping didn’t respond directly; although the fingerprints didn’t match, the possibility of an accomplice couldn’t be ruled out. Her boyfriend had a key to the apartment, so he remained a suspect.

“Captain Zeng,” said Li Hui, returning after checking the surveillance footage.

“Did you find anything?”

“I asked at the surveillance room. There are cameras at the front door, in the ground floor lobby, and in the elevator, but there’s no surveillance in the stairwell, rear entrance, or corridors of the apartment building,” Li Hui explained.

“So as long as the suspect knows the layout of the apartment or has scoped it out in advance, it’s entirely possible to avoid the cameras,” Tian Li observed.

“Apartment buildings differ from residential buildings—there’s usually only one or two blocks, and security tends to be weaker,” Han Bin noted.

“From the available footage, did you spot any suspicious individuals?” Zeng Ping asked.

“No,” Li Hui answered.

“I think Miss Chen should review the footage herself, in case she recognizes someone,” Han Bin suggested.

Zeng Ping nodded. “The likelihood of this being committed by someone familiar is quite high.”

“I’ve already copied the video files,” Li Hui said.

Chen Luyan then sat at the computer to review the surveillance footage.

Han Bin and the others stood a little distance away, quietly discussing the case.

“Captain Zeng, there are serious gaps in the surveillance. Any suspect with a bit of intelligence would take the stairs, so it’s unlikely we’ll be able to identify anyone from the footage,” Li Hui remarked.

“I still think her boyfriend is a suspect. There’s no sign the lock was forced—without a key, you couldn’t get in to install the camera,” Tian Li said.

“But the fingerprints didn’t match, right?” Zhao Ming countered.

“Someone else may have touched the camera before it was installed, perhaps even the vendor’s fingerprints,” Tian Li suggested.

“If that’s the case, the situation becomes more complicated,” Li Hui said.

“Han Bin, what’s your take?”

“I examined the camera earlier. I think the camera itself is a promising direction for investigation,” Han Bin replied.

“How do you propose we investigate?” Li Hui asked.

“Since the camera was placed, it had to be monitored. The footage would have to be either copied or uploaded online to reach the suspect,” Han Bin explained.

“That’s a good angle,” Zeng Ping analyzed. “If the footage was copied, the USB drive would need to be swapped regularly, meaning the suspect may have visited the victim’s home more than once. If it was uploaded online, the camera would need to connect to a wireless network.”

“I checked—the camera appears to upload footage via the network. The suspect could monitor using a phone or computer,” Han Bin said.

“The camera was so well-hidden, surrounded by walls. A distant network signal wouldn’t reach it, so the suspect must have used a nearby network,” Li Hui observed.

Han Bin took out his phone, reviewing the photos he had taken of the camera. He examined them closely. “342.”

“What does that mean?” someone asked.

“It’s the network account used by the camera,” Han Bin explained.

“Are you talking about 342?” Chen Luyan interjected.

“Do you know whose wireless network that is nearby?”

“That’s mine. I always connect to network 342,” Chen Luyan replied.

“Who else knows your network password?” Li Hui asked.

“Just me and my boyfriend,” Chen Luyan answered.

“Did your boyfriend help set up the network?” Han Bin asked.

“No, it was already installed by the landlord when I moved in,” Chen Luyan said, suddenly recalling something. “Right, the password was set by the landlord too, so he knows it.”

“So, besides Miss Chen’s boyfriend, the landlord is also a suspect,” Zeng Ping concluded.

“But the landlord doesn’t have a key,” Tian Li pointed out.

“That’s an assumption. The landlord doesn’t have a key now, but he did before. He could have installed the camera before Miss Chen moved in,” Han Bin said.

“That’s right,” Tian Li realized. “We should compare the fingerprints from the camera with the landlord’s.”

“Miss Chen, have you wiped the router?” Zeng Ping asked.

“The router’s on my desk. Whenever I open the window, dust settles on it, so I clean it often,” Chen Luyan replied.

“Routers are usually installed by the network company’s staff, so the fingerprints collected might not belong to the landlord,” Han Bin noted.

“Think carefully—did the landlord leave anything in your home, or leave any fingerprints?” Tian Li prompted.

Chen Luyan frowned, thinking for a moment, then shook her head. “I’ve been renting for two months now, and I did a thorough cleaning after moving in. I can’t recall anything offhand.”

“When you signed the lease, did you leave a fingerprint?” Han Bin asked.

“I remember now. When we signed the contract, I wasn’t planning to add a fingerprint, but the landlord insisted we both do it, saying it was more secure,” Chen Luyan recalled.

“Bring the contract.”

Moments later, Chen Luyan brought out the lease agreement. The fingerprints were stamped in ink, so there was no need to collect them—they could be directly compared.

After careful analysis, Lu Wen confirmed, “The fingerprint on the lease matches the partial print collected from the camera. This individual is highly suspicious.”

Only a partial fingerprint was obtained from the camera, so Lu Wen couldn’t be absolutely certain it was the same person.

But for Zeng Ping and Han Bin, that was enough.

The chance of two different people sharing the same partial fingerprint in a single case is negligible.