civil forensic

Chapter 222 Breakthrough
Luminol reagent is a reagent that is often used to visualize blood in film and television works.

In the early years, luminol still needed on-site configuration, but now there are already packaged finished products available.

Luminol has a super ability to examine bloodstains.

How strong is it? The bloodstains from a few years ago can be revealed if there is no special treatment.

And even if the blood is diluted 100 million times, that is, one drop of blood is one bathtub of water, it can still be easily detected by the luminol test.

Therefore, trying to wash off the blood with water is basically futile in front of Lumino.

This is also why homicide in the home is generally not recommended.

Luminol is a very cheap reagent. With 0.1 gram of luminol, 5 grams of sodium carbonate, and 6 ml of hydrogen peroxide, you can fill a bottle of 100 ml of luminol solvent.

It still uses the method of spraying for inspection, and it doesn't take long to spray a room.

Moreover, the current DNA technology is also very advanced, with high sensitivity. The bloodstains sprayed out by Luminol just softened the bloodstains, and you can easily make DNA by sweeping them with a cotton swab.

Moreover, general toiletries and cleaning products are difficult to clean the blood to the extent that luminol cannot detect it.

To interfere with luminol, oxidizing agents must be used, the most common ones are bleaching powder and potassium permanganate, but they cannot completely interfere with the luminol reaction, because the luminescence time of hemoglobin and the interference item are different, experienced field surveys, It's easy to spot the difference.

As for the bathroom in the hotel, these things are naturally not used.

What's more, the cleaning lady in the bathroom has never been known for her diligence.

Jiang Yuan took several photos before Lumino's glow ended, and then said: "Master, you can turn on the light."

"Okay." Wu Jun turned on the light with a smile on his face.

"So happy?" Jiang Yuan took out his gloves and a mask, put them on, then took out a cotton swab, and began to operate carefully.

If nothing else, these bloodstains are the key evidence in this case.

In Bai Yuequn's complete set of lies, there is no room for the blood of Yuan Yutang and her boyfriend.

Wu Jun looked at Jiang Yuan rolling the cotton swab with a relaxed face, and said, "Let him act like a ghost, and drink the old man's dick-washing water."

"The DNA test hasn't been done yet." Jiang Yuan reminded.

Wu Jun chuckled, drew a circle with his hand, and said, "Unless both of their hemorrhoids burst, this must be the place where Bai Yuequn cleaned the blood."

Jiang Yuan gave an "en" and made a slight correction: "Unless a customer's hemorrhoids exploded in the bathroom in recent years, otherwise, this is basically the scene of Bai Yuequn's clear blood."

"It can be more rigorous, but... where are the bloody clothes and the murder weapon?" Wu Jun frowned slightly.

In the city, bloody clothes and murder weapons are more difficult to deal with. Jiang Yuan didn't have any thoughts for a while, but said: "First break through Bai Yuequn's alibi."

"That's right. If this Xu Yi doesn't say anything, he should open his mouth with the accomplice in the murder case." Wu Jun still has a lot of experience.

Criminal suspects cannot see lawyers during the interrogation stage, and can only listen to what the police say.Therefore, if you don’t study hard, kill someone or accompany someone to kill someone, you will be exploited because of poor information.

Bai Yuequn's fencing teammates looked easy to bully.

……

evening.

Lei Xin made a careful plan and was ready to interrogate Xu Yi himself.

Lei Xin started out as a pre-trial judge in his early years.In fact, when there was a pre-trial department, the policemen who could enter the pre-trial department were all with excellent professional ability.His teeth yellowed by bongs are also the proof of history.

After carefully reading the DNA report again, Lei Xin walked into the interrogation room with high spirits.

Xu Yi was tall and thin. After his hands and feet were locked by the interrogation chair, he looked like a giraffe playing with a bondage. Only his head was stretched out.

"Do you know what we want to ask?" It's not the first time Lei Xin interrogated Xu Yi. He had a short conversation before, but this time he sat across from him with a smile on his face and put down a thick stack of documents. .

Xu Yi couldn't help looking at that pile of documents, which seemed to be a lot of evidence and testimony, and he couldn't help but guess in his heart.

After a while, Xu Yi turned his gaze back and said, "I know, you want me to retract the confession."

"I want to save your life, kid, and I don't want to see you as a scapegoat." Lei Xin decided to play tricks, first took out a few photos from surveillance video, and said: "These are the photos of Bai Yuequn's stepping spots we captured. Photo."

The Picture Investigation Squadron found a lot of videos, and Lei Xin showed him one by one.

Xu Yi looked at it, turned his head and said, "Don't put it on, that's the nearest movie theater on Bar Street, it's just going to a movie, it's nothing like a stop."

"You have something to say in this explanation." Lei Xin seized the opportunity to praise Xu Yi, and then showed the picture and time of the damage to the monitor in No. 2 projection room.

Then release a photo of Bai Yuequn entering and leaving the theater at about the same time.

Seeing the back, Xu Yi simply closed his eyes and said, "If you really can't find the murderer, you can just arrest us and make so many inexplicable things."

Looking at his expression, Lei Xin silently took out his trump card and said, "I have a DNA report here, which was collected from the hotel room you stayed in that night. How do you explain this?"

Xu Yi was taken aback: "What do you mean?"

"In your hotel room, there are bloodstains from the two deceased, quite a lot." Lei Xin said flatly, "It should be the blood that Bai Yuequn didn't clean at the scene."

Xu Yi hesitated for a moment, then said, "You lied to me."

"Suppose I lied to you. Now I go to the bathroom of the hotel where you are staying to find bloodstains. Do you think I can find the bloodstains of the two deceased?" Lei Xin held the DNA report in his hand and didn't give it to Xu Yi.

Xu Yi couldn't hold it anymore.

"Do you really want to be in prison for the rest of your life like Bai Yuequn?" Lei Xin began to use a sympathetic offensive.

Xu Yi's expression changed slightly, and after a while, he said, "There is still work."

"what?"

"Bai Yuequn promised me, don't talk nonsense, and find me another job later. If the two of us are criminally charged, it will be difficult to find a job." Xu Yi's voice was very soft.

Lei Xin was overjoyed, as long as he opened his mouth, he would be able to ask questions later.

Lei Xin said: "Then let me ask again, during the movie screening that day, did Bai Yuequn watch the movie with you in the No. 2 screening room, and did he leave during the screening?"

Xu Yi said: "I don't know."

Lei Xin couldn't hold back immediately, if he was allowed to eat a person, he would be able to grind Xu Yi finely in his mouth.

"I really don't know." Xu Yi said: "When I entered the screening room that day, I felt a little tired, so I fell asleep. I don't know when Bai Yuequn left or if he left."

This sentence cannot incriminate Bai Yuequn, but it is enough to disintegrate Bai Yuequn's alibi.

Not only Lei Xin, but also the people watching the surveillance couldn't help being happy.

Lei Xin continued his efforts: "Then on the way from the theater to the hotel, did you notice what Bai Yuequn dropped?"

Xu Yi said: "No."

"What about the smell? Don't you smell it?"

"I was wearing a mask. N95, it didn't smell anyway."

(End of this chapter)