With less than two months before the start of the lay judge system, about 20 Diet members formed an informal nonpartisan group Wednesday to postpone its launch, noting some potential jurors may not want to participate, or don't feel qualified.

While agreeing it is important to make the judicial system more open to the public, the legislators said several elements of the system — including confidentiality rules and trial lengths — need further discussion.

They also said they don't believe the public will be prepared enough to pass judgment in serious cases by the time the system starts on May 21.

The group said it wants to attract more members to discuss their legal options before the system starts running.

Under the system, six citizens are selected at random to try cases involving heinous crimes under the guidance of three professional judges. The nine-member panels have to determine not only guilt or innocence, but also any punishment involved.

Decisions are to be made by majority vote, and at least one of the real judges must be in the majority. The lay judges will be selected from a list of eligible voters, but politicians and people in other certain professions will be excluded from duty.

"I believe it's a problem when the system forces a person who doesn't want to be a lay judge to serve," said Kokumin Shinto (Japan New Party) legislator Hisaoki Kamei, who leads the group. "It is against people's freedom of thought and I think it is unconstitutional."

The Supreme Court says that a typical case will take about three days to conclude, but Democratic Party of Japan member Kazuhiro Haraguchi, also in the group, said he was doubtful it would happen that way.