Before the case is revealed, no police officer is sure whether their direction is correct.

The two plainclothes "undercovers" lurking at the trap of Chongqing Mansion and other police officers lurking at Chongqing Mansion to participate in two cases and two missions are not sure whether they can really get evidence of the murder of the unfilial couple while taking down the "illegal infringement of tenants' rights" gang.

Or, whether Yao Qingtian, who was waiting for the red light on the side of the road in the high-definition photo they received, will really target this couple, come to Chongqing Mansion, conduct on-site inspections, plan missions, and try to implement them... and even fail to be captured in the end.

The paparazzi of the Criminal Intelligence Division were not sure whether the footage captured by the special cameras in their bags would be useful for the case, and whether Officer Yi Jiayi could really find some important clues that they had not discovered through repeated observation.

Xu Da, a professional leader of the Criminal Intelligence Division, would never just sit in the car and stare at people like ordinary police officers.

Although this method is the most labor-saving, it has long been exposed by newspapers and movies, and many smart people being monitored can easily find it.

Xu Da and his female police officer Ada dressed up and followed Yao Qingtian around. Sometimes they were a couple quarreling on the street, sometimes they were a middle-aged man playing chess with his grandfather and a bored woman waiting for a haircut in a hair salon, sometimes they were a single man living across from Yao Qingtian and a good mother picking up her child from school... They

were not worried about being discovered by Yao Qingtian, but they would never be remembered by Yao Qingtian. They were just the most ordinary citizens in this city, as natural as trees in the city.

After watching Yao Qingtian all night and one morning, Xu Da and Ada did not find anything suspicious about Yao Qingtian.

Previously, they had teamed up to follow a target of Organized Crime and Triads who was about to rob a gold shop, and a narcotics dealer from the Narcotics Division. Basically, the look and the movements of these people were different from the others, and they could clearly feel the evil of these people.

But Yao Qingtian was different. He got up early in the morning and went to his mother's house in Sham Shui Po to help her. He was busy until breakfast, and looked no different from every other frustrated middle-aged man.

"I heard that he has been judged by the police officers who followed him last time as someone who does not have time to commit crimes. Do you really want me and Ada to continue following him?" Xu Da asked hesitantly when he called his superior.

He and Ada are the best expert police officers in the team. Is it really okay to use them to follow such a person?

"Follow us. The one who made the request is Yi Jiayi Shazhan from the West Kowloon Serious Crime Unit. Superintendent Wong said that Yi Shazhan must have her reasons for wanting us to transfer the best people, which are you and Ada." The officer opposite repeated what he said to dismiss Superintendent Wong, and then said:

"Sir Wong also said that if no problems were found, it must be our fault, and it is impossible that Yi Shazhan from their Serious Crime Unit had a problem."

"..."Xu Da.

……

……

The detectives of Group B in the Yau Ma Tei Police Station had no doubts about what they were doing.

Liu Jiaming took Ajie from the Forensic Department and quietly ran to the outside of Yao Qingtian's house. He used the professional video camera of the Forensic Department to take a long-distance video of Yao Qingtian's walking posture.

After Yao Qingtian left, he ran to the door of Yao Qingtian's house to collect Yao Qingtian's footprint information.

I took it back to the Forensic Department for analysis of the footprints and gait. Everyone has a different point of contact when walking, and the direction of the soles and heels of the footprints caused by the gait are also different. This is a very important clue to determine whether the murderer and the suspect are the same person.

Recently, the research on gait and footprints by Da Guangming has achieved initial results, and he has also published professional articles in relevant magazines at home and abroad.

The only problem is that the accuracy of the footprint analysis report can only reach about 98% consistency between the suspect and the murderer at most. There is no possibility that this evidence is 100% consistent.

…

In the office, Brother Yue took Gary to review Yao Qingtian’s schedule. When the poisoning of wild cats in the street park happened, where did Yao Qingtian live, what was his schedule, and what happened to him?

Before and after the poisoning of pet dogs in the seaside park, where did Yao Qingtian live? According to the testimony of his neighbors, what was his daily life like, whether he would go to the seaside park for a walk, etc.

During the time of Liang Xiaofu’s death, Yao Qingtian also lived alone, and did not go to his mother’s house in the three days before and after - the person who ran to help his mother every day did not go during this period. He has no alibi, and his behavior pattern has changed.

When the murder of Miao Liqun occurred, Yao Qingtian also had no alibi...

The documents were printed out one after another, just waiting for colleagues in the Criminal Intelligence Division to get some new clues, and then compare them with these investigation clues against Yao Qingtian.

...

Uncle Jiu and Sanfu went to where Yao Qingtian lived six months ago and visited his neighbors and former teachers and colleagues to learn about Yao Qingtian and whether he had any suspicious behavior or remarks.

After visiting the old residence, he quietly rushed to the new residence. Only when Yao Qingtian was not at home, he visited and collected clues.

Jiayi and Liang Shule set off for Chen Xiaomi's appointment and met in a small coffee shop in Central.

"What would Madam Yi and Officer Liang like to drink?" Chen Xiaomi asked with a smile, without any gloomy expression of being forced to take a vacation.

"Vanilla latte."

"Iced Americano."

As soon as the two of them placed their orders, Chen Xiaomi took out a few things from a large leather bag she carried with her, placed them on the table, and pushed them to Yi Jiayi.

The two police officers looked at the things wrapped in the bag on the table, and Jiayi asked in confusion: "What is it?"

"This is a feather duster stained with Yao Qingtian's blood and palm dandruff.

"This is the cup that Yao Qingtian used to drink water."

Chen Xiaomi pointed to another bag and said:

"The corners of the pages of the books that were cut out here should also have Yao Qingtian's saliva. He was used to dip his fingers in saliva when turning pages.

"There are also a few strands of hair in this bag, which are also Yao Qingtian's. They seem to have hair follicles. You can also ask the police officer in the laboratory to help test them."

"!" Liang Shule's pupils shrank, and he looked at the rich evidence in front of him with some disbelief.

"How did you get it?" After being surprised, Jiayi immediately became concerned about this issue.

The colleagues in the criminal intelligence department have been keeping an eye on Yao Qingtian, but they didn't find that he met Chen Xiaomi.

And... a chicken feather duster?

How could there be such a thing stained with his blood?

"It was Yao Qingtian's student Li Baoyun who helped me get it." Chen Xiaomi then recounted how she found Li Baoyun, how she deceived Li Baoyun's trust, and how she finally got these things.

Jiayi didn't know what expression to make.

Chen Xiaomi finished speaking, and Jiayi immediately handed the things to Liang Shule, "Take it back to the police station and give it to Brother Da Guangming immediately, and send it to do DNA and other tests as soon as possible."

"Yes, madam." Liang Shule stood up and left.

Yi Jiayi was still sitting at the table, hesitating about how to communicate this to Chen Xiaomi. After a few seconds of silence, she spoke first:

"Lawyer Chen, first of all, thank you very much for handing these things over to the police."

Chen Xiaomi smiled immediately when she heard what Yi Jiayi said, but Jiayi went on to say:

"But as a lawyer, you should understand the risks of obtaining evidence in this way."

"I understand. Once your test results match, I will go to Li Baoyun to discuss this matter and will not let this evidence become the 'Fruit of the poisonous tree'."

As a lawyer, Chen Xiaomi certainly understands that evidence obtained through illegal means is called the 'Fruit of the poisonous tree'. tree, is invalid, but in an emergency, she has been a lawyer for so many years and knows too well that operations and rules cannot be completely overlapped. Seeing that Yi Jiayi is still a little worried, she continued:

"The principle of 'fruit of the poisonous tree' has exceptions in law. The first exception is if the method I use to obtain evidence can also be obtained through normal behavior. For example, even if I don't coax Li Baoyun to find evidence, she will secretly obtain Teacher Yao Qingtian's DNA vector and hand it over to the police because she saw the murderer's photo in the newspaper and thought he looked like Teacher Yao Qingtian;

"The second exception is the purged taint exception. It means that I obtained Yao Qingtian's DNA vector through inappropriate means, and this evidence cannot be used. But afterwards, the police proved Yao Qingtian's suspiciousness through their own means, and then obtained Yao Qingtian's DNA vector through formal means. Although the evidence I provided cannot be used as evidence in court, the evidence provided by the police can. And I provided the DNA vector relatively early, which can help the police confirm earlier whether Yao Qingtian is the murderer. It can also help the police obtain DNA evidence obtained by formal means earlier.

"The third exception is that these evidences can also be judged as independent aid, that is, in addition to being obtained from me, they can also be obtained from other qualified witnesses. Lawyers can use this to determine the validity of the evidence.

"Officer Yi, please believe that I am not completely unconcerned about these things. "

She had also thought carefully about how to use these evidences.

Yi Jiayi nodded. The reason why the police had not used this method before was because of such concerns. The police's rules for collecting evidence are very cautious and strict. Hong Kong attaches great importance to human rights and has strong supervision over the judiciary. If such things are accidentally touched, not only may the evidence be unable to be used, but it may also cause the police and judicial personnel to lose their jobs. Although

Chen Xiaomi said this, Jiayi could not fully guarantee that the evidence provided by the other party would be used for judicial prosecution.

And...

"Lawyer Chen, we also have to consider the safety of you and Li Baoyun."

"Safety? "Chen Xiaomi was stunned for a moment. This seemed to be something she had not thought deeply about.

"Li Baoyun does not know the seriousness of this matter. If it is accidentally exposed and Yao Qingtian finds out what she and you have done, Li Baoyun will be the first to be in danger.

"Although we have judged that Yao Qingtian is such a cautious suspect and would not kill people in his social circle, especially those so close to him, he is after all the suspect in such a brutal murder. What if he is desperate?

"First of all, Li Baoyun is unaware of the situation. She has no idea who she is facing or what she is doing. Secondly, she is only in her teens and is naive. She is completely defenseless against this society and the people around her..."

Jiayi's expression gradually became serious. Now they are setting a trap for Yao Qingtian. They cannot brazenly return to Yao Qingtian, but someone must protect the safety of Li Baoyun and Chen Xiaomi.

She frowned and became worried.

"What should we do? I--" Chen Xiaomi heard what Yi Jiayi said, and instantly realized that although as a lawyer, he had considered the risks of success of this matter, but he did not take into account these possibilities.

"First of all, you can't take the risk to see Li Baoyun again. If you are discovered by the cunning suspect, both of you will be in danger." Jiayi pursed her lips and thought for a while,

"I will handle it. Thank you again, Lawyer Chen, but next time if you have any ideas, please call me in advance, please believe me."

After that, Jiayi stood up.

"Understood, then next time I..." Chen Xiaomi hesitated.

"And please, Mr. Detective, stop investigating Yao Qingtian. The suspect is very cautious and will find out. "And it is very likely that Yao Qingtian will suspect that it is the police's tracking behavior. "Just enjoy your vacation from now on. I will go to see Li Baoyun, and I will handle this matter, don't worry." "

Thank you, Officer Yi." Chen Xiaomi stood up and said goodbye to Yi Jiayi in a hurry.

Yi Jiayi was anxious to go back to discuss this matter with Fang Zhenyue. She waved to her and strode out of the café.

Chen Xiaomi looked at Yi Jiayi's back, as if she saw the light called "reliable".

...

At Li Baoyun's house, the Filipino maid who was preparing to clean the dust in the room couldn't find the tools inside or outside, and couldn't help scratching her head:

"Why is the feather duster gone? "

...

On her way back, Yi Jiayi received another piece of news:

two professional police officers from the Criminal Intelligence Department had lost Yao Qingtian.