Fang Rui led the team to Zhang Mingli's house. Her home had bedrooms upstairs and downstairs, but only the side bedroom upstairs had a bookshelf, which was a wall-mounted one, not very large in size.
They dismantled the bookshelf and found a large hole in the wall, originally meant for an embedded electric meter box, which was later presumably moved, leaving a big hole. Inside the hole was a cassette tape and a shopping receipt.
The cassette tape had been stored for many years, and it was uncertain whether it had deteriorated.
The receipt listed the items purchased: two buckets of tung oil, one bucket of alcohol, and one bottle of disinfectant, dated August 7, 2004. However, it did not mention the buyer's name, only the store name: Sunshine Department Store.
The receipt was wrapped in plastic film.
"Wang, take it for testing to see if there are any fingerprints on it."
"Okay."
The cassette tape was unable to be played, but the black plastic tape was intact. Fang Rui sent the tape to the technical department to see if it could be repaired.
The fingerprint test results came out quickly. There were fingerprints from two people on the receipt, one of which matched Zhang Taotao's.
With the efforts of the technical department, the cassette tape was also successfully repaired.
Inside was a recording of an argument between Zhang Taotao and Zhang Huanhuan.
"Brother, you lied to me! I read Li Bao's diary, he never cheated on me, he loved me deeply. The reason he neglected me during that time was because he and Mingli did a paternity test, and Mingli is not his daughter. I never cheated, so why isn't Mingli Li Bao's daughter? Brother, you switched my child, didn't you?"
"Huanhuan, I had no choice. The one-child policy was so strict, and our Zhang family only has me as the son. If I didn't have a son, our family's lineage would be cut off. Anyway, your child and my child both share our bloodline, so what's the big deal about switching them?"
"Brother, why did you slander Li Bao for cheating? You took away my son, why did you also destroy my family? I'm your own sister, why did you treat me like this?"
"That's because you two didn't love each other enough. Otherwise, how could I have easily sowed discord with just a few words? Li Bao was too petty, you should have divorced him long ago and found a better man to marry."
"Brother, I've had enough of you. You ruined my sister's marriage, and now you won't even spare me. I'm going to turn myself in. I'd rather go to jail than give you another penny."
"Huanhuan, you and I are in the same boat now. If you go to the police, we're both done for. You're a murderer, and I helped you bury the body. We'll both end up in prison."
"Brother, please dig up Li Bao, I want to give him a proper burial. He didn't betray me, I can't let him be buried here like this."
"No way! You'd better behave, or I'll kill your son."
The recording ended abruptly here.
These pieces of evidence were enough to prove that Zhang Taotao had switched the children and was involved in the burial.
Zhang Taotao was brought back to the interrogation room again.
Zhang, with his arms crossed, coldly looked at Zhang Taotao: "Zhang Mingli has regained her memory and told us everything that happened at the time. There's no point in denying it anymore, just confess your crimes."
Zhang Taotao laughed at Zhang's words, "Mingli has been amnesiac for so many years, and suddenly she remembers everything? And what can a six-year-old remember? Little comrade, your logic for solving cases isn't very good. How can we, ordinary people, trust you?"
"You—"
Fang Rui placed the shopping receipt in front of him.
Zhang Taotao's smug smile froze. He had written this receipt to ask Zhang Huanhuan to reimburse the expenses. He didn't expect Zhang Huanhuan to keep it all these years and now the police had found it.
Zhang Taotao quickly calmed down. It didn't matter, there was no name on it. It had been so many years; the store certainly wouldn't remember him.
Fang Rui noticed Zhang Taotao's lips move, knowing he was about to make excuses, so he reminded him, "There are your fingerprints on this receipt, you can't deny it."
"I bought things for my sister, isn't that allowed? This receipt was for asking her to reimburse the expenses."
"We also have a cassette tape."
Fang Rui played the recording in front of Zhang Taotao.
At first, Zhang Taotao remained composed, but the more he listened, the worse his expression became.
"Officer, a recording can't be used as evidence, can it?" Zhang Taotao still refused to admit it.
"When a recording meets the conditions of authenticity, legality, and relevance, it can be used as valid evidence," Fang Rui rebutted, "Wang Pandi's testimony can prove you were the mastermind behind the child switch, and this recording can corroborate that; the purchase receipt for the tung oil, the recording, and Zhang Mingli's statement can all prove you were involved in the case back then!"
Zhang Taotao instinctively wanted to refute, but Zhang interrupted him, "Even if you refuse to admit it, with these pieces of evidence, we can solve the case without your confession."
Faced with so much evidence, Zhang Taotao had no choice but to confess his crimes, "Yes, I switched the children. But I'm the only son in our Zhang family, wanting a son to carry on the family line, is that wrong?"
Zhang Taotao had consulted a lawyer. Switching children like this, the court wouldn't be too harsh. As long as he insisted that Zhang Huanhuan agreed to the switch, the court wouldn't sentence him too severely.
Fang Rui was amused by his righteous defense.
"Yes, your family's lineage is noble, but you stole someone else's son, isn't that also someone else's lineage?" Zhang mocked, "If you can't have a son, it's probably because your ancestors think, with you as a descendant, they'd rather have the lineage cut off."
Zhang Taotao was so angry that his veins bulged, but he clenched his fists and remained calm.
"Officers, I admit to switching the children. I need to educate you on some legal knowledge. Assisting in burying a body is punishable by up to three years in prison, or detention, or surveillance, with a maximum sentence not exceeding ten years, and the statute of limitations is fifteen years. This case has passed the statute of limitations. There's no need for you to investigate who buried the body, as the perpetrator won't be punished anyway."
Zhang Taotao smiled coldly.
He could go to prison for protecting the family lineage, which was a family honor. But he would not admit to any other crimes, as the police would never uncover the truth.
At that moment, the interrogation room door was knocked on.
Fang Rui paused the interrogation and went outside.
Outside was Mu Mian, full of excitement.
"Fang Rui, my luck this time is really good. I've found evidence that can put Zhang Taotao, this scoundrel, behind bars."
Seeing Fang Rui go out but not returning for a long time, Zhang Taotao's hands kept rubbing, feeling increasingly anxious.
The door creaked open, and Fang Rui re-entered.
Zhang Taotao was startled by the sudden sound of the door opening. But he quickly regained his composure.
"Zhang Taotao, do you know how Li Bao died?"
"How would I know that! I said, I don't know about this matter."
"His cause of death was suffocation. Tung oil blocked his respiratory tract, preventing oxygen from entering his lungs, causing him to suffocate." Fang Rui said.
Zhang Taotao's face changed drastically.
"Impossible! He was killed by falling! My sister pushed him down the stairs, and he hit the floor and died! My sister told me herself." Zhang Taotao denied vehemently, then regretted it, suspecting that Fang Rui had deliberately given him the wrong cause of death to provoke him.
Li Bao was clearly killed by falling, how could it be suffocation? Zhang Taotao recalled the feel of the body at the time, it was warm... Could it be that he had actually killed Li Bao himself?
"We have to thank you for that. You did a thorough job of preserving the body, preventing it from completely decomposing, so we could find the real cause of death."
"So what, do you have evidence?"
"Of course." Fang Rui stared at Zhang Taotao, "We found your blood on the deceased."
