Diary of a Criminal Investigator

Lu Chuan had already thoroughly inspected the office door lock.

Verified that there were no signs of forced entry.

There were a total of 7 keys to this office; Director Chen and four doctors each had one, and another key was inside Director Chen’s office.

Additionally, the hospital’s Public Security and Protection Department also had a spare key.

However, this was the current number of keys, since there had been staff transfers among the healthcare doctors, and others had keys which were returned and never redistributed—this can’t be verified now.

Zhang Hui had already interviewed the healthcare doctors and conducted a detailed investigation.

So far, there was no evidence of any of the five people betraying for personal gain.

The doctors and Director Chen left separately, and Lu Chuan started pacing in the office.

The office wasn’t big, just under a hundred square meters.

Upon entering, there was a filing cabinet on the left and an office area on the right.

Conventional crime scene techniques like fingerprints and footprints weren’t even considered by Lu Chuan.

There would surely be no results.

If Director Chen and the other 5 truly didn’t commit the crime themselves,

then Lu Chuan now needed to find out how the suspect entered the office.

The side of the office corridor was windowless, only walls.

The only entrance was the door.

But there were high-definition surveillance cameras in the corridor, and there were no strangers entering from that night until the next morning.

The cleaning took place in between, but only mopping was done.

Zhang Hui had also investigated the cleaning staff, an aunt who had been doing cleaning in the hospital for seven or eight years.

On the east-facing side, there were two windows, but bars were installed long ago.

Even though it was the second floor, there was no chance of entering through the windows.

Yang Sen had carefully checked these windows; there was no issue with the security bars, and no climbing marks on the window.

I didn’t wear any, and thoroughly checked; Yang Sen’s field investigation seemed solid, with no traces left on the windows.

And this afternoon, while waiting for off-duty hours, Lu Chuan had also walked around outside the building.

There were no trampling marks on the lawn near the healthcare office.

No one had been beneath the windows recently.

So, how exactly did they get in?

The doors and windows were intact.

It seemed that unless the healthcare doctors committed the crime themselves, there was no other reasonable explanation.

However, the maternal and child healthcare doctors had good pay.

Even though the 78 birth certificates could sell for a lot, was it worth risking their lives for the five healthcare doctors?

It doesn’t make sense logically.

The healthcare doctors are more aware than anyone of the consequences of issues with birth certificates.

It isn’t just about paying or handing over something.

It means jail time.

The healthcare doctors have stable career positions, for just this money...

It doesn’t add up.

Of course, if it were a solitary act, it would be easier to explain, but five acting together...

Seems very unlikely.

"Chuan, you know what I’ve been going through this week, right?"

Zhang Hui followed Lu Chuan: "I’ve wracked my brains and still couldn’t figure out how the thief did it!"

How did they do it?

There has to be a way.

If they couldn’t get in through the windows or the door...

Then it must be from above or below.

It’s unlikely to be from below.

All floor tiles, Lu Chuan had just walked over them.

Then it must be from above.

"Brother Hui, has the ceiling been taken apart?"

The ceiling?

Zhang Hui looked up at the white ceiling: "We haven’t checked that; it can’t be, right?"

"It’s just a false ceiling, and above it is the floor slab..."

Zhang Hui never considered this angle.

"Brother Hui, bring a stool over; we just need to check it out."

There wasn’t really any other option.

The windows had security bars and showed no signs of tampering.

The office door area had high-definition cameras, and no possibility of footage being tampered with.

The ground was tiled, so they could only check above.

Zhang Hui brought over a chair, and Lu Chuan stood on it to reach the ceiling.

Opening a partition from the corner, Lu Chuan peered in, and could just manage to get inside to check the situation.

This look wasn’t reassuring.

"Brother Hui, I’ve found something!"

After an hour, with the joint effort of a dozen criminal policemen, half of the ceiling had been taken down.

"It was cut open here."

Above everyone’s heads, near the wall, was an air duct.

The hospital’s property manager was also called over.

"This is an exhaust system installed in the hospital a few years ago."

"Each office has one."

This exhaust system had a large pipe, and the healthcare office’s air outlet was in the center of the office’s ceiling.

However, on the side near the wall, there was a significant opening.

"The suspect... entered through here?"

Zhang Hui never thought the thief really descended from above.

Lu Chuan had already started investigating at the cut duct area.

There were quite a few fingerprints.

"All collected, now trace the duct."

Of course, they wouldn’t send someone directly into the ducts.

The Criminal Investigation Team first checked the office’s side using a reconnaissance robot. By having it walk through, they can see inside.

Lu Chuan had just called Yang Sen, who, along with Yang Lin, was driving over.

Lu Chuan’s work was quickly done.

The suspect left fingerprints on the cut edges of the duct.

By the time Yang Sen arrived, Lu Chuan had finished the examination.

The rest was to trace the duct back to the initial entry point.

Soon, the location was ultimately identified in the women’s restroom on the same floor!

In the restroom, Lu Chuan found a cut passage at the entrance, just like before.

Now, the method the suspect used to enter the office was found, but the case wasn’t solved yet.

Was it an inside job or an outsider? It’s still impossible to determine.

The corridor surveillance cameras could see in front of each office door, but the restroom was in the corner, just out of view.

"I’ll head back to analyze the fingerprint identifications to see if we can pin down an identity."

"Alright, I’ll conduct some inquiries here to see if there are any leads."

The two then parted ways.

Zhang Hui promptly reported to Qin Yong.

Though the case hasn’t been cracked, at least there’s now a significant lead.

The main focus is on whether Lu Chuan’s fingerprint identification results can match the suspect.

If it matches, all the better.

But if it truly doesn’t match, the police still have a way.

Despite not being captured on the corridor’s surveillance, the suspect had to leave the hospital from the restroom on the day of the incident.

At most, the surveillance the day before and after the incident will be fully reviewed.

One by one; they’ll find the suspect eventually.