"Xiao Wang also really likes fidgeting with computer software. Whenever our county had a case requiring collaborative investigation, it was Xiao Wang who arranged for it to be handled," Yan endorsed Xiao Wang while simultaneously justifying the reputation of our county's only two trace investigators.
Wang Zhong, however, smiled shyly and humbly said, "What I do can't compare to Doctor Jiang. You do fingerprinting hands-on, while I mainly just run the fingerprint database."
The fingerprint database is constantly updated, and the primary responsibility for this lies with the trace evidence police officers from various locations. They are in charge of taking photographs of collected fingerprints, archiving them, writing descriptions, and sometimes even manually processing them before entering them into the fingerprint database. Additionally, fingerprints from older cases that predate the use of computer systems also require manual verification and other procedures in order to be included in the database.
Periodically running old case fingerprints through the database is one such method. Suspects who were previously unmatched might one day be caught for drunk driving or a brawl, and then be identified. Even crime suspects who obtain something like a temporary residence permit could lead to a lonely fingerprint finding its match, fulfilling the role of a matchmaker.
Furthermore, a person who commits a crime in another region might not be found in the local fingerprint database but may have fingerprint information in a database elsewhere. Such fingerprints don't necessarily have to be complicated; oftentimes, when trace evidence officers receive a request for assistance, they just need to roughly mark the key points using the most traditional methods, then run the database. Throwing a dart and seeing if it sticks can sometimes yield a hit.
Running the database has also become a routine for most ordinary trace evidence officers. If Jiang Yuan didn't have the system, it would be good enough to just be able to run the database for the first few years. Therefore, he said warmly and sincerely, "It doesn't matter if it's a white cat or a black cat; as long as it catches mice, it's a good cat."
Wang Zhong immediately felt that this young man, Jiang Yuan, was decent and easy to work with, so he made an even more self-deprecating comparison, "In terms of catching mice, you're a Bengal cat, and at best, I'm just a Ragdoll."
The people present looked at Wang Zhong's cheeks, rough from years of working on-site and staying up late, and then at the fair and gentle Jiang Yuan, sinking into a diplomatic reverie.
"You just mentioned a case?" Wu Jun reminded him.
"Right, right, right." Wang Zhong organized his thoughts before saying, "It's an old case from over a decade ago, a case that left a deep impression on me when I was running the database. The case itself is simple: a group of high school graduates were drinking farewell drinks, got drunk, and got into a conflict with a passing young man. As a result, they were hit with a stool and ended up flipping over. Sadly, the student who got hit was blinded in one eye, and that escalated to grievous bodily harm."
"You said blinded in one eye, and I remember now. Back when the college entrance exams were in July, scores were coming out and the weather was hot, everywhere you had students causing trouble after drinking beer. The college acceptance rate was low that year, and students who had nowhere to go, including those who were retaking a year, were looking for trouble everywhere. The worst case was this one; the student who got hit was a top student and had gotten into a junior college. I guess getting beaten up had something to do with it too." Doctor Wu reminisced about the past with some emotion, "It was my mentor who did the forensic examination."
"That's the case. At the time, we speculated that the suspect might have been a visiting student from another region or someone who came to work, and ran away after the incident," Xiao Wang nodded.
Yan Ge felt that the case from over a decade ago was a bit too remote for him since he hadn't seen the files, so he asked directly, "Wasn't there a special case team set up?"
"The county set up a special case team, but mainly for investigation and inquiries; they never zeroed in on a suspect," Wang Zhong replied.
"What about at the city level?"
"It didn't reach the city level."
"Back then, we didn't implement decentralization. Qinghe City Bureau basically didn't handle casework," Wu Jun explained. In earlier years, provincial and city bureaus provided guidance on casework rather than handling cases directly. To put it plainly, they did not directly manage cases.
For instance, the Provincial Bureau, with a staff of just a few hundred people, couldn't handle major cases due to its small size. Even regular work required borrowing staff from districts and counties; it was more practical to leave cases to the districts and counties and focus on technical organization work themselves.
The staffing situation at the City Bureau was a little better, and in recent years they had been required to take a more hands-on approach in handling cases and so forth. However, in backward areas like Anping City and Shannan Province, what should be done and what could be done in reality were two different things.
Therefore, not only did the aforementioned grievous injury case from over a decade ago not reach the City Bureau, but even now, serious injury cases must have a significant impact before a city-level special case team is organized. Of course, if it had been a murder case, that would be a different story.
"There were also issues with the fingerprint evidence," Xiao Wang continued, "At that time, fingerprints were lifted from the stool leg used as a weapon by the suspect, but the stool leg was made of round steel tubing..."
"Oh…" Yan and Jiang Yuan simultaneously showed a dawning realization. The photography and lifting of prints from cylindrical surfaces have always been a major challenge in criminal investigation fieldwork. The curved shape causes serious deformation of the fingerprint, and the curved surface causes significant reflection issues during photography. Although it's still possible to obtain fingerprints, their completeness and accuracy are substantially compromised.
"Back in the day, fingerprints were probably fixed using sectional photography, so the deformation must be significant..." Yan Ge guessed, then sighed, "We even trained in methods like using a special device to photograph the curved surfaces of cylindrical objects, which rotated and snapped pictures. In the end, only the provincial capital bought one. You had to jump through hoops just to use it, but now it's simpler—just open your phone and take a panorama, which is even better than that machine's results!"
Jiang Yuan couldn't help but give a wry smile as he casually opened the software on his computer and looked up the case file.
The four fingerprints left by the suspect quickly appeared on the screen, drawing everyone to lean in and take a look.
Within just a few seconds, Yan Ge and Wang Zhong both abandoned hope.
The clarity of the image was passable, but there were many interruptions. Needless to say, making a judgment would surely be extremely challenging. The most problematic aspect was that both sides of the fingerprint showed obvious spreading; the lines in the distorted areas were distinctly wider and thicker. With such conditions, the first step would necessarily be to correct the distortion of the image before even attempting to mark the fingerprint. That level of difficulty was certainly advanced.
In Yan Ge's assessment, forget about him and Xiao Wang, even if it were sent to the city or even the provincial authorities, the outcome was uncertain.
Wang Zhong, who had been following this case closely since the initial search, eagerly said, "The advantage with this case is that except for these few continuous prints, all others found on the weapon have already been excluded. Additionally, a sketch artist was consulted at the time to draw the suspect. Although years have passed, having both the fingerprint and a sketch should make confirmation easier."
Those present couldn't help but nod in agreement. This was indeed an advantage. The number of cold cases that could be solved through fingerprinting was limited, and securing a conviction even less likely. Plus, having a sketch, along with the involved parties and eyewitness testimonies, would mean that if the fingerprint matched, suspects could be apprehended and the case closed immediately.
Of course, this all hinged on matching the fingerprint.
Old Yan, Xiao Wang, and Wu Jun all turned their gazes to Jiang Yuan.
Jiang Yuan couldn't help but chuckle to himself.
"It seems that Jiang Yuan is confident," Xiao Wang suddenly felt a bit envious of Jiang Yuan.
"I'll give it a try," Jiang Yuan said with a smile. The main reason he was smiling was that the fingerprint left by the suspect happened to be a loop pattern. If not for that, he might have had to hand off the case.
As for the difficulty, based on his recent experience with fingerprints, it seemed within reach. Just not something he could achieve overnight.
At that moment, Wu Jun laughed heartily and said, "Solving a case is one thing, but rest is another. Let's not rush into it today. It's a cold case after all; a day or two won't make a difference..."
His interruption was deliberate. No matter what, Yan Ge and Wang Peng were the forensic experts in the team, but Jiang Yuan was a forensic doctor and also his disciple. It wasn't appropriate for the younger forensic doctor to be working on fingerprints in front of two experienced forensic police officers.
"Indeed, you guys must be exhausted from dealing with bodies these past few days, take it easy," Yan Ge laughed and then left with Wang Zhong.
After Wu Jun and the others left, he took a sip of water from his cup, looked at Jiang Yuan, and said, "No need to rush, it's almost time for lunch. Pack up, eat. Are you going to stir-fry something yourself today?"
Jiang Yuan really wasn't in a hurry and asked, "Can I stir-fry something myself at the canteen here?"
Wu Jun waved his hand dismissively, "No need to bother them, the K-9 unit has a kitchen."
Jiang Yuan: .ʕʘ‿ʘʔ.