civil forensic

Chapter 24

In the afternoon, after tidying up a bit, Jiang Yuan and Wang Zhong rode their own electric bikes to the area where the crime occurred.

The small red-brick building located in the suburbs is still quite old-fashioned. The two-way, four-lane small road is planted with dubious trees on both sides and in the middle. The sparse shrubs prove that the maintenance level of the neighborhood is very average, but it took time to plant it. The trees still maintain the basic quality of the residential area.

This is the outer suburbs of the county, but because there are some factories nearby, it is more prosperous than many places in the county.

Of course, just prosperity and not prosperity.Looking around, there are patches of old residential quarters and new temporary buildings, which keep the environment at the level of the old industrial area.

Small shops Small shops are the mainstream business model in the neighborhood, and the fronts of small shops are mostly old-fashioned, which is difficult to arouse people's desire to consume.

And these shops that are too lazy to clean up the curtains also have no desire to install cameras.

The municipal construction here seems to have stagnated with time.The old road traffic is still well maintained, but it is about the same level as it was in the past, and newer or better things have hardly appeared.

The neighborhood where the incident occurred was more desolate than other neighborhoods on the same road.There was only the main entrance, where a few old men gathered, looking at everything around them with suspicious eyes.The other two gates of the community are now handcuffed with big chains.These actions, which were originally convenience measures, are now regarded as the culprit.

"What are you doing?" Seeing Jiang Yuan and Wang Zhong riding electric bicycles to enter the door, an old man bravely blocked the way with his body.

"Police." Both of them came here in casual clothes, so they took out their police officer IDs and showed them.

The old man frowned: "I heard that now there are people who make fake police officer certificates to deceive people. Are you a liar..."

"Call 110 if you don't believe me." Wang Zhong said, and then said: "We are here to re-survey the site, are you willing to be witnesses?".

The old man took out his mobile phone and was about to call 110. He was taken aback when he heard it: "What?"

"Let's go in and have a look at the scene and see if there is any evidence. You just stand inside and watch, and then you can just sign your name." Wang Zhongyan explained succinctly.

China's criminal case scene inspection witness system requires the investigative agency to invite third-party natural persons to witness the inspection and inspection activities of the crime scene.This is completely different from the American judicial system that often appears in film and television dramas.

The United States adopts the method of police self-certification, stipulates the on-site recording system, and requires the police to self-certify the fairness and standardization of on-site inspections.In contrast, RB and Russia also adopt the on-site inspection witness system, but they are different.

To put it simply, countries with a witness system require that the evidence collection of each case be watched by outsiders, so as to prevent perjury as much as possible.In countries like the United States that do not have a witness system, each police officer is required to restrain himself. Once false testimony occurs, all cases handled by the police officer can be doubted.

Although there are often imperfections in practice, as small policemen, Wang Zhong and Jiang Yuan both follow the norms.

In fact, finding one or two passers-by at random is still not very in line with the spirit of the on-site investigation witness system. Fundamentally speaking, this system requires people who have a certain understanding of the scene, a certain understanding of criminal investigation and are related to the case. For unrelated personnel to be witnesses, it would be even better if they could witness the survey site many times throughout the process.

However, when the public does not understand, witnesses have no financial compensation, the police are too busy, and the judicial system is not demanding, such a requirement is obviously unrealistic. Witnesses who will leak information.

The two old men who are under the retirement age but started to retire early due to the decline of the company are quite good.It is also more compliant than using auxiliary police as witnesses.

The old men at the door may be idle incubating eggs, or they may be full of interest in the murder case in the community. After asking for a while, they reluctantly watched the two young old men enter the scene of the crime together. floor.

Wang Zhong took the key from the office, lifted the security belt casually, opened the door and entered, and then locked the door to change clothes.He asked the two retired old men who were under the age to stand in a corner, not allowed to speak, not move, and not allowed to take pictures.

"Where do we start?" Wang Zhong didn't plan to come, and he didn't have the confidence to come for a re-examination, but Jiang Yuan had an idea, so he still came along.

Jiang Yuan looked around and said slowly: "Let's start from the beginning."

Following his voice came the translucent interface that the system slowly unfolded:

Mission: start from scratch

Task content: Conduct repeated investigations on the scene of Xue Ming's case to obtain clues and evidence.

Jiang Yuan stared at the system interface for a few seconds before it disappeared.

"Start from the beginning?" Wang Zhong listened a little silly, then leaned closer to Jiang Yuan, and asked in a low voice: "Is it necessary?"

"Try it." Jiang Yuan said, spread out the equipment, then picked up a glass from the shoe cabinet at the door, soaked some water with a cotton swab, and wiped it gently.

Although the time period of acquaintance, my qualifications are a little deeper.But deep down, Wang Zhong is convinced of Jiang Yuan.For skills such as fingerprints, the gap in strength is too easy to show.

After standing still for a moment, Jiang Yuan's actions made Wang Zhong speechless.

Ordinary surveyors wipe the cup, or in other words, when the surveyors in Ningtai County wipe the cup, they directly use a cotton swab to wipe around the mouth of the cup. Although this method can also wipe out possible DNA, it has never It's all just a shorthand.Or rather, a common practice of incompetence.

Jiang Yuan's rubbing method, but Wang Zhong has only seen it on rare occasions.I saw that Jiang Yuan first dipped the cotton swab in water, and then squeezed it until it was half dry.When wiping, he will not wipe a large area, but choose a position on the mouth of the cup, rub the cotton swab up and down, and wipe it three to four times evenly, trying to wipe the DNA that may exist on it.

After wiping one point, Jiang Yuan wiped again at a certain point after a period of time. After several times, the DNA extraction of a cup was completed.

Doing so will naturally take more time than swiping around in a circle, but the probability of extracting DNA is also much higher.

Although Wang Zhong had never tried Jiang Yuan's method of swabbing DNA before, but based on the details Jiang Yuan showed, Wang Zhong knew that Jiang Yuan's rank was really higher than the team's current survey.

For example, a cotton swab that is semi-dry but not wet transfers DNA more easily than a cotton swab that is dry rubbed, and it is also easier to transfer DNA than a cotton swab that is saturated with water.The so-called don't get along with the mud, don't get wet.

Using the way northerners understand it as an example, a cotton swab is like a bath towel. If you rub your dry skin with a dry bath towel, you won’t get much off the skin, and a bath towel soaked in water will only slip back and forth. If you can't remove much dirt by rubbing, you have to use a half-dry towel to rub the skin that is half-dry and not wet. The effect is the best, and the most things can be rubbed away.

To use the way non-northern people understand it as an example, a cotton swab is like a tongue. If you wipe your tongue dry to lick the dry skin, you won't be able to lick much. The effect of moistening the tongue with water is not good. The half-dry tongue must lick the half-dry skin for the best effect and the best state of friction.

Similarly, Jiang Yuan's method of wiping at one point is more effective than the method of wiping around a circle.Still using the way northerners understand it as an example, this is like rubbing at fixed points with a scrub towel, and using a scrub towel to pull a big saw, and the rubbed things cannot be counted.Using the way of understanding of non-northern people as an example, licking a spot is more effective than licking all over the place.

Jiang Yuan really has something, so Wang Zhong stopped talking, and simply followed Jiang Yuan to help him.

After working in the trace inspection position of the Criminal Division Squadron for several years, Wang Zhong has long understood that some things, when you see them, you feel that you understand them, or even understand them well, but it doesn’t mean that you can think of them, and it doesn’t mean that you can think of them. Use it right, and using it right doesn't mean you'll use it well, and using it well doesn't mean you'll use it quickly.

Using a way that anyone who has participated in nine-year compulsory education can understand as an example, there are a total of five formulas in Eulerian geometry, and a total of one hundred and ten formulas in Newton’s three laws. Normal people can understand it after listening to the class, but they may not be able to understand it when they see the questions. No matter which formula you use, you may not use it right if you think about it. If you use it right, you may not use it well, and if you use it well, you may not use it quickly.

Wang Zhong also appeared on the scene all the year round to do surveys. Seeing that Jiang Yuan could do it meticulously, quickly, and quickly, he was too surprised.Fortunately, when he was doing fingerprints, he was used to helping Jiang Yuan. The first time he was a stranger and the second time he was acquainted, and gradually he became smoother. He even felt quite comfortable doing it.

(End of this chapter)