1. Yes, you should know everything in your file. Make sure to bring it with you court, along with copies of anything you will want to show as evidence and give to the Judge or opposing counsel.
2. If you can't recall something, simply state "I can not recall." That is an acceptable answer. If they ask regarding a specific document, state that "the document speaks for itself and I refer you to examine it."
3. This depends on the mistake. If you try and introduce evidence not previously every discussed or produced in discovery, the Judge will merely keep the evidence out. There is no Jury. The judge will already understand the case and will merely be looking at you during trial to see if there is something he is unaware of. This is your time to plead your case to the Judge. Be sincere, honest and explain your position clearly. Practice what you plan to tell the Judge (your mini speech) to a friend or family member. You may only get 30 seconds for your opening or closing statements, so make it short and to the point. Write it out and bring it with you, as well.
4. You should already have a list prepared of who you plan to call at trial to ask questions. Have the questions you plan to ask the creditor written out. Bring all the documents with you, and make copies of those you actually plan to use. For example, a copy of bill should be copied 3 times, if you wish to discuss it so you can give a copy to opposing counsel and the trustee and the Judge. You will keep the original to look at yourself. If you wish to show the Judge something, always state first "May I approach the bench, your honor?" Be respectful and never do anything without the Judge's permission. He will tell you when you may speak or he will ask you questions directly.
5. Jury trials are only permitted if both sides agree or if there is some issue of fact that exceeds the bounds of the bankruptcy judge. Therefore, in your situation there will be no jury trial even if the creditor would like one.
6. Watching an adversary proceeding would be a great idea, if you can find one. They are not publicly advertised; however, if you go to the Bankruptcy Court house and go to the area outside the Judge's court rooms they will have a list of all the proceedings happening each day. You can check through the paper list (or the electronic docket - if their court house has upgraded--it is a little computer podium) and see if anyone has an adversary proceeding trial. You may luck out and find that one is happening that day. If you do attend, show up at least 20-30 minutes early and when you go in the court room explain to the court clerk before the judge comes out and ask if it is ok if you observe and that you are merely trying to learn. You may want to ask any lawyers there too, so they don't eject you. Make sure to where a suit, as well. Federal Judges do not like people wearing street clothes in their courtrooms. If they say it is ok, just be polite, quiet, and sit in the back.
Consult with your attorney about the mediation issue. If the mediator has already been paid for and scheduled, you are required to attend. If it was agreed to and scheduled, you will be required to pay for half of the mediator's fees. If it has not be scheduled, explain to the opposing counseling you need to cancel it, or ask if they can cover the full amount of the fees.
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