According to Peter Takeo Okada, who is president of the [Catholic Bishops’ Conference of Japan], the lay judge system “does not fit in with the mission of the clergy from the start.”
Okada gives two reasons for the conflict. The first is that the basic thinking behind Christianity is the notion of forgiveness. The clergy must preach that whatever the sin, God has mercy for sinners who repent, and therefore, that mission does not go hand in hand with handing down a conviction in a crime.
The other point is the unique position that bishops and other clergy members hold. Their beliefs are formed around the notion that God alone knows whether a person is guilty of sin. Therefore, the clergy do not judge whether a person is good or evil based on information that person has gleaned.
Officials say it would be difficult for the clergy to shift away from such thinking only while they serve as lay judges.
Further down in the article:
In the United States, which employs a jury system, few states make an exception for clergy and the U.S. Conference of Catholic Bishops has issued no instructions to dioceses.
Some suggest that in the United States the clergy have a stronger sense of sharing responsibility as individual members of society.
There’s another major systematic consideration, which Asahi hasn’t picked up on, and which most people overlook when comparing the Japanese lay-judge system to the American jury system.
In the US, a juror’s duty is essentially to look at evidence, to compare that evidence to a list of criteria for legal guilt or liability, and to either decide whether there is reasonable doubt that those criteria exist (in a criminal case) or to decide whether there is a preponderance of evidence that those criteria exist (in a civil case). The judgment of guilt or lack thereof is simply a function of the rules imposed by the system and is not technically up to the juror to decide: the juror is there to decide whether the evidence is credible enough. This is why the judge is generally careful in issuing jury instructions to guide their decision. (Note that, depending on jurisdiction, American jurors can often legally find a “not guilty” verdict if they object to a guilty verdict for any reason, but this ability is disdained by the trial courts and usually isn’t pointed out to the jurors.)
On the other hand, as described in a recent American law journal article (which is horribly edited, confirming all my prior suspicions about Penn kids), Japan has taken a more collegial approach where the roles of judge and jury get blissfully muddled.
At the close of the trial, the panel of judges and lay jurors will retire to deliberate. The Lay Assessor Act provides little guidance for how deliberation should proceed. This question was left to researchers at the Supreme Court. Though every detail is not finalized, summaries of their meetings indicate that some important decisions have already been made. Researchers determined that jury deliberations should open with undirected, free conversation about the trial and evidence, after which judges can clarify disputed points, review the evidence, and explain the law. Great emphasis was placed on guarding against the possibility of judges leading lay jurors to the judges’ interpretation of events. For example, judges will be asked to state their opinion only after the lay jurors have stated theirs. In the case of a disagreement between a judge and the lay jurors, if the judge can recognize the lay interpretation as valid, she should defer to the jurors. Judges should state only their opinion and avoid actively persuading jurors, especially at the beginning stages of the deliberation. However, if a judge cannot compromise on a disputed point, she is permitted to vigorously argue her view.
In short, the professional judges and lay judges (or jurors or assessors or whatever you want to call them) are supposed to be on an even footing in the whole procedure, and they are supposed to reach the decision through a holistic assessment of the situation as a group. In this regard, the lay judges are actually taking a much more active role in administering justice, so it’s little surprise that the Catholic bishops are nervous about subjecting clergy to those duties.