personally I truely think it's great that you tried to stay out of the whole thing, it's not right to take sides imo. but again it was said again you can take the 5th ammendment and stay silent and at least tell the judge you do not wish to testify agianist your mother.

Everyone who is saying plead the 5th: You're dumb, the 5th amendment only applies to incriminating oneself and even then only in criminal cases. Everyone who is saying he can't be compelled to come into court for a civil case: YES, yes he can. If he was issued a subpoena then he has to. OP: You're not required to testify AGAINST her, you're required to tell the truth. All being issued the subpoena means is that you are listed on your father's witness list. He is probably doing that just to intimidate your mother and you can offer to be on her witness list as well to basically make the effect go away.

I'm pretty sure that there is a way to tell the court that you don't want to testify plus I'm also pretty sure that the attourney has to ask permission of the witness before adding that person as a witness.

Go to court tell the truth from as neutral point as possible and let the jury decide, FYL indeed but it is best to remain neutral through the entire situation, also if you wanted to avoid going to court consult a lawyer. Most people on this sight are not lawyers and reviewing the comments will not help (besides most contradict each other).

Then continue to be neutral by telling the truth and saying what you saw. Your mom's probably stealing a shitload of money from your dad. It wouldn't surprise me if she divorced him for some lowlife, and they're living off the alimony.

one two three four FIZITH!

Might have already been said, but just plead the fifth for all the questions

You have to show, and you have to answer, but that doesn't mean you have to let your dad get off scot free for this. Tell him that if he makes you testify you'll never speak to him again. If he values you over his lawsuit (and he thinks you're serious) he'll do it. (If this is a criminal case, though, even this won't help--that's up to the district attorney.)

go to jail. if you're selfish enough to testify against your MOTHER so you don't have to go to jail, you're a freaking jerk.

I'm not sure if you have to testify, I think you can decline, you should ask your mom's lawyer, or any lawyer really, about that. But if you have to show up as a witness you don't have to say negative things about her. You swear to tell the truth, so tell the truth. If your mother is a kind woman, tell them about that, if she is funny, tell them about that. You don't have to say bad things about her just because your Dad called you for his side. Hell, if you get called to the stand, after they swear you in, you can ask that it be put on the record that you had originally wished to remain neutral and are very uncomfortable testifying one way or the other.