Advice from non-Japanese who have been divorced in Japanese courts

Japanese courts may have different rules than courts in your country.  Here is advice on divorce in Japanese courts. Be sure to check with your lawyer and confirm anything here that you plan to use in court.

1. Japan's equivalent of a no-fault divorce is the Divorce By Mutual Consent.  Once you get to court, it may be the case that one person must be declared the loser, i.e. the cause of the divorce. Depending on the "cause" the loser may have to pay consolation money to the winner. Be prepared for your spouse to make untruthful claims against you. There seems to be no penalty for perjury in a civil case (although there may be in a criminal case), so even if you can prove that your STBX's claims are false, s/he loses nothing in the eyes of the judge.  It certainly seems to not make much difference regarding custody if the parent who commits perjury is in possession of the child and isn't committing atrocities while raising it. So you may want to be prepared with claims of your own.
2. The previous point may make it important to file first in Japan, with a claim that your spouse is the cause of the divorce.
3. If you don't like the current judge, stall. They seem to switch in and out on intervals. (Not sure the length - maybe 1 year.)  Consult with your lawyer on tactics.  As a last resort, one way known to work is to get a new lawyer.  (Well, at least it worked for on Japanese mother we know.)
4. If your lawyer is not being aggressive enough, or is not taking the positions you want them to take, consider a new lawyer.  Conversely, be aware that if the opposition lawyer is too responsive to your suggestions of visitation or other reasonable access to your child, the kidnapping parent may change lawyers until finding one who agrees with them.
5. If court investigators need to interview you and your spouse, the person who brought the main suit will be interviewed first.  If you hold a counter suit or are the defendant, forget it. The person who is interviewed second will have to spend part of their time defending the claims brought by the first person rather than making claims against the first interviewee.  The first interviewee does not seem to have to respond to the claims of the second interviewee. Therefore it's extremely important that you file first, although if the Japanese parent holds physical custody, it is likely they already have a lawyer who knows this, and will file first.
6. If you get to see your child thru supervised visitation at court be prepared to fill 40~45 minutes.  Pretend the 2-way mirror/cameras don't exist. There will probably be a court official in the room with you so you could get him/her to join in. There are toys, games and so on which the court supplies. You should also bring along some extra things which your child might enjoy playing with. (ie; cards to play snap or make a card house etc.)  If your child has special toys they enjoy playing with you, be sure to bring those too.
7. During mediation, interviews and in court, take notes of anything unusual - discriminatory or ridiculous comments by mediators or investigators, giggling or smirking court officials etc. If need be get your lawyer to bring in a laptop and take notes at family court. You may even want to record these on tape in for future reference.
8. Don's say or do anything outside of court that your spouse could use against you.  You probably want to buy a small video camera and audio recorder to have with you every time you meet.  Or bring a friend as a witness.
9. If you are the provider of income in the family, you will have to pay child support during the course of the trial.  On the order of 3-man per month.