"Who has this man been in contact with since yesterday?"

The policeman hurriedly said: "I have not been in contact with others, and after you said yesterday, deputy captain, we will send people to strictly guard him, and we have not given him the opportunity to contact outsiders."

Sun Jianguo asked again: "Who has Zhang Hanyang been in contact with?"

"At present, we are investigating, but we have not found anything for the time being, and the ......possibility of being instigated has basically been ruled out."

Sun Jianguo looked at him indifferently and said, "The accurate result I want is not a vague situation like basic, possible, and probable, let me find out." ”

"Yes, I'll arrange it." After the policeman finished speaking, he trotted away, Sun Jianguo squatted on his body again, checked the man's body, at this time there was no movement of the person, I put my hand on his nostrils, I didn't feel the flow of breath at all, obviously dead.

Sun Jianguo watched it for a while, and said to himself: "The blow is fatal, the wound is in the temple, and the attack is very accurate, do you know that you are going to die and want to pull a cushion?" ”

Then he stood up and said to the detention center police who stayed at the scene: "I will thoroughly investigate this matter, but don't let go of anything that is possible!" ”

"Yes!"

Sun Jianguo's face was ugly, he didn't stay any longer, turned around and left the canteen of the detention center, and I hurriedly followed. In the process of walking out, I met Liu Yefang, who rushed over after hearing the news, and saw that she was about to ask Sun Jianguo, so I hurriedly pulled her down and roughly explained the situation, and pointed to Sun Jianguo, who was walking in front, and said: "The vice captain is very irritable now, don't look for him." ”

Liu Yefang obviously didn't believe it either, and asked suspiciously: "Zhang Hanyang killed someone?" ”

"That's what the police in the detention center said, when we arrived, Zhang Hanyang had already been escorted back to the shift room, and the man was almost cold."

"No, is he taking revenge on the police? Or do you want to pull a cushion on your back before you die? By the way, have you checked who Zhang Hanyang has been in contact with from yesterday to today? Maybe it was instigated by someone else. ”

I pointed to Sun Jianguo, who was walking in front, and said: "The deputy captain has already sent someone to investigate, I believe that there will be a result soon, but I think it is unlikely that he will be instigated, Zhang Hanyang will be sentenced by the court at the end of the month, and it will definitely be a death sentence, he has no need to toss himself during this time." ”

Liu Yefang thought for a while and had no choice but to say: "I hope so, if it is instigated by someone, then the murderer is likely to be in the detention center, and the man's death may be his murder." ”

When I returned to the office, I saw what Zhang Bin was talking to Sun Jianguo, yesterday Zhang Bin took someone to the traffic police team to check the bus, and now there should be a result.

The two were silent for a while, and Sun Jianguo suddenly said, "Didn't you find any results?" ”

Zhang Bin said a little relaxed: "Yes, but I think the more perfect it is, the bigger the flaw, because the people who can do this are undoubtedly the internal employees of the bus company, and it is difficult for others to do this." ”

"You may not know one thing, just now, one of Yang Ziqiang's horses died, and now the specific reason is unknown, so the situation is not easy to say."

Zhang Bin asked in surprise, "Dead?" How did he die? ”

I explained on the side: "There was a fight with Zhang Hanyang when he was grabbing a seat, and he was immediately seriously injured, and when we arrived, people were no longer dead. ”

"Instructed or unexpected?"

I shook my head and said, "It's still under investigation, and it's hard to say the results." ”

Liu Yefang gave Zhang Bin a look, and changed the topic: "Deputy captain, the murderer has done a perfect job in all aspects, but this is the biggest flaw, and I feel more and more now that the real murderer is hiding inside the bus company." ”

Sun Jianguo didn't answer, leaned back in the chair and rubbed his temples for a while, and then said slowly: "You go to investigate first, you can't invest too many people in the early stage, otherwise you will startle the snake, if you lack manpower, just transfer directly from the team." ”

"In addition, the focus is on interrogating the other three horses under Yang Ziqiang, if Zhang Hanyang is instigated, he is definitely one of these three people, and maybe even all three of them are involved."

"Bring the polygraph that has just been dispensed, I heard that you can take a polygraph with something, but I don't know if it's reliable."

I didn't expect that the Songhai City Public Security Bureau also distributed a lie detector, that thing I saw at the police academy, when I only knew about this thing, I thought it was amazing, I could tell the truth from the false, and then after knowing the principle, I found that I thought too much.

The psychological changes of people when lying will inevitably cause changes in some physiological parameters (changes in skin electricity, pulse, blood pressure, respiration, etc.), which are generally only restricted by the autonomic nervous system and not controlled by the brain consciousness. Polygraphy actually measures the changes in physiological parameters caused by psychological stimuli, rather than the "lie" itself.

And this thing is not omnipotent, it cannot be said that all lies can be broken, it should be said that within the scope of the suspect who has been identified, he can be found out basically through this test of criminal psychology. There are two reasons for this, firstly, whether the polygraph can function properly, and secondly, it is closely related to the external environment of the test, the individual state of the testee, the level of the tester and the design of the question.

There is also a relatively rare situation, the murderer has excellent psychological quality, or has serious psychological problems, and can calmly tell lies when facing the polygraph, and the polygraph cannot detect physiological fluctuations, so it will not sound an alarm, which will also make the murderer temporarily escape.

Liu Yefang had obviously heard of this thing, frowned and quickly relaxed, the time was very short, but it was Sun Jianguo who was discovered.

"What? Having a hard time? ”

Liu Yefang hesitated for a few seconds, and simply said: "Indeed, if the murderer's psychological quality is excellent, even if he uses a lie detector, it is useless, and this thing has a lot to do with the questions raised by the tester, and I have not used the lie detector many times, I am afraid it will be very difficult."

Sun Jianguo waved his hand indifferently: "It's okay, just treat it as a study, there are no professionals in this area in the bureau now, you have the foundation to learn quickly, and then you will hand it over to others." We all retire one day, but crime doesn't stop. ”

"Okay, then I'll try, but the results can only be used as a reference, not as a conclusion." Liu Yefang was still not at ease, so she thought about it and said again.

"Of course I know this, machines are dead, people are alive, and I definitely believe what you say more than the results of the two."