Chapter 400: Borrowed Knife Murder

On the interrogation chair, the man shouted angrily, eager to prove his innocence.

Xu Mo simply gave a faint nod and put away the series of evidence—hair strands, cigarette butts, palm prints, cloth pieces—that he had just brought in from the scene.

These items were no longer needed; after realizing his accomplice had indeed confessed, the man stopped being defiant.

Xu Mo was not surprised by the man's words.

In fact, after reading Ren Qin's Confession Statement, Xu Mo realized the statement was problematic; she was only threatened to give a one‑sided account, merely to lessen her sentence.

That was easy to see.

If Ren Qin truly had been threatened not to speak about it, she would not have been so calm at first; when she first saw the officer, she would have been extremely conflicted and nervous, appearing as someone who wanted to tell the truth but dared not.

The problem lies in her overly calm demeanor; clearly the matter directly involved her, and she was not being coerced.

As for the claim of coercion in the statement, that must be an excuse; she only turned on the man at the last minute to reduce her culpability.

That is also why Xu Mo, after reading Ren Qin's Confession Statement, was still willing to give the man a chance.

Bringing the murderer to justice is what he should do, but Xu Mo judged the man only committed involuntary manslaughter and did not coerce anyone, so there was no need to add another charge… even if he killed someone.

Although he thought so internally, Xu Mo did not verbally agree with the man.

"Was the idea of disguising the deceased's death as a suicide suggested by Ren Qin?" Xu Mo showed a hint of doubt: "That doesn't make sense; the dead was her son, why would she go out of her way to exonerate you?"

A mother helped a stranger kill her own son and even fabricated the suicide scene… that truly makes no sense.

"It makes sense!" the man nodded heavily.

He exclaimed emotionally: "That child wasn't her biological son; she is infertile, and the boy she raised was adopted, so they have no blood relationship at all… Moreover, after learning he wasn't her flesh‑and‑blood child, they constantly quarreled, fighting every few days. The conflict between them was deep; Ren Qin was repeatedly beaten by the adopted son for no reason, and his attacks were brutal."

After speaking, fearing Xu Mo wouldn't believe him, the man added.

"You can verify this! Do a DNA test, or ask the neighbors; everyone knows about this!"

With that, it could be explained… Xu Mo couldn't help but stroke his chin.

The deceased was not Ren Qin's biological child; they had no blood relationship.

Moreover, after learning there was no blood tie with Ren Qin, the deceased harbored considerable hostility toward her, which explains why Ren Qin was willing to exonerate her lover rather than seek justice for her son.

Xu Mo put himself in Ren Qin's shoes.

When the adopted son grew up and learned he wasn't her biological child, resentment brewed inside, and he even repeatedly assaulted her, making the scandal widely known and turning the neighbors into onlookers.

Anyone in that situation would probably feel grievance.

Raise a child for decades only to produce a backstabbing wolf? Who could stand that!

So there is a reason for not seeking justice for the son but choosing to exonerate an outsider…

Suddenly, a thought flashed through Xu Mo's mind.

Longstanding grudges, killing with a borrowed knife!

He recalled a detail.

"Did Ren Qin tell you that the deceased was going on a business trip?"

"Yes," the man nodded, then recalled: "She told me her son would be on a week‑long business trip and asked me to stay at her house for a few days. I went without thinking much, but her son rushed back early the next morning, and I ran into him. My relationship with Ren Qin was a secret underground affair… and then I fought with her son."

Thus… Xu Mo felt he needed to reexamine the case.

He needed to sort out who was the principal offender and who the accomplice.

Xu Mo pushed the door and left the Interrogation Room.

"Wang Dachuan, Xiao Zhang, both of you, come here for a moment."

Office.

Xu Mo assigned a task to Wang Dachuan and Xiao Zhang respectively.

"Wang Dachuan, go to the deceased's company and ask where the business trip assigned before his death was headed, and how many days it was supposed to last."

"Xiao Zhang, visit the residential complex where the deceased lived and ask the neighboring residents whether they heard any fighting noises from his house."

"Yes!" the two said in unison.

After receiving the tasks, the two left the Police Station one after another.

Immediately after, Xu Mo returned to the Interrogation Room where Ren Qin was, took several strands of her hair, then went to the morgue where the deceased's body was kept and likewise took a few strands of the deceased's hair.

A corpse can also be used for DNA testing; skin tissue, hair, blood, and so on can yield DNA samples… provided the body hasn't been deliberately destroyed, such as by dissolving it in sulfuric acid.

At present, this corpse hasn't been tampered with and died recently, so DNA samples can still be extracted.

Collecting the two hair samples is mainly for a paternity test to verify the man's claim.

An expedited paternity test can yield results in as fast as three hours.

Xu Mo looked up a place that could perform a paternity test, then left the Police Station with the two hair samples.

Testing Center.

Xu Mo presented his credentials, provided the two hair samples, and explained that he was investigating a case and needed the results as quickly as possible.

The staff at the Testing Center wasted no time; upon receiving the hair samples, they immediately began the analysis.

About three hours later.

The Testing Center staff arrived before Xu Mo with the results.

"Officer, the results you requested are in. After testing, the DNA probes from the two hair samples show multiple mismatches; we can confirm that the owners of the two samples have absolutely no blood relationship."

Xu Mo took the test results.

"Absolutely no blood relationship… does that mean they are definitely not biologically related?"

"Yes."

"Thanks."

Xu Mo returned to the Police Station with the test results.

Inside the Police Station, Wang Dachuan and Xiao Zhang had already completed the tasks Xu Mo assigned and returned, waiting to report to him. When they saw Xu Mo back, they immediately leaned in toward him.

Team Leader Xu, I asked around, the deceased's superior said it was just that the deceased had to entertain the client well that night, entertaining the client at most only takes half an evening's time, there's no such thing as a business trip at all, if he wanted to go back, he could go home that same night.

I also visited the deceased's neighbors, they said they had heard multiple times noises of fighting coming from the deceased's home, it was the deceased beating Ren Qin.

"Then everything matches up……" Xu Mo murmured.

"Sure enough, it's killing with a borrowed knife!"