There Is No “Why” in the World#8
Proof in Court
A has been summoned to trial. He is accused of murdering B. The prosecutor says:
“B was A’s business partner. The two of them had been fighting intensely over a large sum of money. A few days ago, a witness even heard A say, ‘That bastard—I’m going to finish him for sure.’”
To some members of the jury, this may feel as though it explains everything. But for the judge, it is not enough. Perhaps the highest priority in the judge’s mind is the question: Why is this person a criminal?
For the judge, that question does not belong to the realm of emotion or narrative. It is closer to a probability game played on a spectrum of data’s resistance to fabrication—a spectrum of “how impossible it is to rig.”
To participate in this game, one must first follow the rules. In court, there is a first filter called admissibility of evidence.
No matter how clear the motive for murder (the “why”) may be, and even if there is a recorded confession in the offender’s own voice saying, “I killed him,” if that recording was collected in violation of procedure, then within the courtroom that data has no value. The court may not be a place that is primarily interested in what actually happened. Rather, it is a system that strictly asks what materials can be admitted within the rules of this game.
If the materials pass this filter, the judge then evaluates their probative value. Admissibility is about “whether this evidence has the qualifications to be brought into court,” while probative value is about “how much this evidence can persuade the judge.”
The prosecutor presents the first piece of circumstantial evidence:
“Right before the incident, the defendant’s phone location was within a 200-meter radius of the crime scene.”
The judge’s face remains expressionless.
Second:
“A trace amount of the victim’s DNA was detected on the defendant’s clothes.”
Third:
“Forty minutes after the incident, a taxi fare was paid with the defendant’s card.”
Fourth, fifth… all the way to the eighteenth.
No matter how many circumstantial pieces of evidence accumulate, the judge will never say, “He is 100% certainly the perpetrator.” But the judge can say something like this:
“If the case has reached this level of resistance to fabrication (a level at which no reasonable doubt remains), then we agree, as a society, to define this person as a criminal.”
Of course, there is no one in the world who can draw a graph showing exactly where this “level” lies on the spectrum in a way that convinces everyone.
The final evaluation of the probative value of the evidence belongs solely to the judge. When the trial ends, what remains is a sentence:
“The defendant is sentenced to ○ years of imprisonment.”
This sentence does not explain “Why did he do it?” But it does announce that a social agreement has been reached regarding “Why is this person a criminal?”