civil forensic

Chapter 896 Suspect

There are many ways to verify the identity of a circuit board. The simplest is to check the serial number and manufacturer's logo.

After Huawei released its new CPU, many self-media outlets adopted this idea. However, if the manufacturer or assembler deliberately conceals the information, or the serial number and logo are eroded, or if the information is missing due to explosion or fire, this trick will be of limited use.

A slightly more complicated approach than checking serial numbers and manufacturer identification is to scan circuit board features, or simply use image recognition technology for identification. This technology sounds very impressive, but it is actually very rare. It is basically only useful within the factory. Outside the factory, for the field of criminal investigation, a database problem is very difficult to use.

In the real world, there are many ways to identify traces and confirm their identity. What really hinders technological progress is database technology.

The identification of footprints, shoe prints, palm prints, firearms, DNA, mitochondrial DNA, tire marks, etc. all face database problems.

The software is easy to make, but the data in the database really needs to be entered one by one by the police.

Over the years, there is one thing that is guaranteed about the fingerprint and DNA database entries, but other types of databases are basically in a state of self-contained development and are definitely not easy to use.

Therefore, Jiang Yuan has used the technology of scanning circuit board features, and it is certain that it is useless.

In the end, Jiang Yuan still arranged and combined the components one by one. In more professional terms, it means observing the arrangement of specific components and connectors.

Circuit boards of the same model can have similar components and connectors, but circuit boards produced by different manufacturers still have differences in the location and layout of different components.

In addition, it is easy to imagine that the circuit boards produced by different manufacturers and the components purchased must be different. And many components are also marked, and they may not be able to be erased.

The circuit boards picked up by the survey team were already in tatters, so in the end they could only determine the model of the circuit board through the components themselves, as well as the arrangement and combination of the components - the first thing was to determine the manufacturer of the circuit board. For most trace inspections, after completing this step, the work is basically completed.

In most cases, the police can simply find the manufacturer and have the manufacturer's technicians determine the model of the wreckage. The method is still the same, but the manufacturer's drawings are more complete and the personnel are more familiar with their own circuit boards.

Jiang Yuan did something similar. After confirming the manufacturer, he sent someone directly there. Then he looked for the same model in the manufacturer's computer and checked the manufacturer's sales records on the spot.

Next, in-house police officers flew to several sellers to extract and investigate further sales records.

three days later.

At 3:30 in the morning, the ringing of the phone woke Zhang Dinghui from his dream.

Zhang Dinghui sat up, completely confused.

The person beside him also turned over and looked at the watch, and said helplessly: "Have so many things happened recently?"

"As long as it's not a bad thing." Zhang Dinghui shook his head and answered the phone: "I'm Zhang Dinghui..."

"...We have determined the suspect's location." The person on the other end of the line was Deng Jiabin, director of the Municipal Bureau.

Zhang Dinghui suddenly came to his senses: "Did you determine the location directly?"

He went to investigate again yesterday. To put it bluntly, he was just a military supervisor. The investigation was still ongoing and there was no news about the suspect at all.

"Yes." Director Deng Jiabin responded, "The suspect used cash when buying circuit boards, but the store owner's cash register records the time. We found an intersection where the suspect walked that day and there was a checkpoint with a human figure. We then contacted the store owner to confirm the suspect's identity."

Zhang Dinghui was actually very familiar with these investigative methods. Hearing this, he said "hmm" and his expression became more serious. He asked, "Who is the suspect? How did you learn the relevant technology?"

"The suspect, Ji Haitao, is a farmer, now 68 years old. He must have learned the technique of making explosives during his militia training. In addition, he has a record of using the Internet, so he must have learned some related techniques." Deng Jiabin answered directly, first stating the main points, and then said: "This Ji Haitao has worked as a construction worker, has also set off blasts in mines, and later led an engineering team. The purpose of this crime is most likely to make money."

Zhang Dinghui breathed a sigh of relief. For a suspect who was seeking compensation, his antisocial attributes should not be that serious. What he feared most was that the other party would set off explosions everywhere for no reason, and this was what he was most worried about in the past few days.

Deng Jiabin knew his leader's thoughts very well, and continued, "We initially determined that the deceased wearing the explosive vest was Ji Haitao's accomplice. From the description of the eyewitnesses at the scene, the two entered the finance office at the time and should have intended to use the explosive vest to rob, but we currently have no idea whether they managed to rob the money or why the explosive vest exploded."

Zhang Dinghui said "hmm" again. Even if the 68-year-old suspect was in good health, it would be difficult for him to rob a gambling house alone, and it would not be easy to control another person either. An accomplice was indeed a more reasonable guess.

"Does he still have explosives in his hands?" Zhang Dinghui asked.

Deng Jiabin: "In this regard, our speculation is similar to the previous one. There should still be some. However, Ji Haitao did not show any inclination to make his own explosives. He mainly obtained materials through some channels. From this perspective, he should not have too many explosives. In addition, Ji Haitao's economic conditions are also relatively average. The explosives he used this time may even be stored in the past."

Zhang Dinghui knew that Deng Jiabin was trying to comfort him, but he did feel a little relieved. Looking at his wife who was sleeping restlessly beside him, Zhang Dinghui stood up, took the phone, and asked in a deep voice as he walked out, "How are you going to arrest the suspect? What's the situation at the scene?"

"The house that Ji Haitao rented is in Anyuewan Community on the outskirts of the city. It's a 28-story high-rise residential building with a tower structure and small apartments. There are many neighbors above, below, and on both sides. There are 6 households on the same floor, and they are all full. One of the rooms is shared by several people. There should be more than 20 people on a single floor." Deng Jiabin only mentioned the residents on the same floor and did not mention the residents upstairs, which made Zhang Dinghui feel a strong sense of crisis.

"We can't arrest him in his residence." Zhang Dinghui said decisively: "Either we lure him out and trap him... or see if you have any other plans."

Zhang Dinghui was considered relatively open-minded. He did not directly give his subordinates a direction to do. Even so, he definitely rejected the method of arresting people in residence.

Deng Jiabin had expected this. Although secretly sending someone to sneak into the suspect's house and arrest him at this point in time is also a plan, the danger of this plan is also beyond doubt.

Even with the help of various advanced instruments, such as thermal imagers, night vision goggles and other equipment, you cannot guarantee how the suspect places and handles the explosives.

What if this person has some paranoid delusions - it can't even be considered a delusion now - and adds some strange switches or methods to the explosives, or even puts a booby trap on the door, then it will be a big problem.

However, it may not be so easy to trick people out.

Deng Jiabin didn't dare to guarantee it, so he could only say: "I will go to the scene to direct the work now and clearly convey your instructions!"

(End of this chapter)