If interrogatories are served upon you and you don't respond, your spouse can obtain a court order to force you to respond. This is expensive and a foolish waste of money, so make sure you and your lawyer answer the questions completely. Another method in the formal process of discovery involves requests for production of documents. This is not a great deal different from the informal method, but like interrogatories, if there is no response, it can lead to court orders, sanctions, possible jail time and a big waste of money. A deposition is a duplication of a court proceeding without a judge.
Depositions have several functions.
First, they narrow the issues so that your lawyer can find out exactly your spouse's position on various matters. For example, if you and your spouse agree that your grandmother's furniture is your separate property, that issue can be eliminated. That is - if a party testifies one way at a deposition, and another way at a trial, it is unlikely that the judge will believe anything the person says. Third, a deposition is very useful in helping the lawyer determine how effective your spouse is likely to be in court. And, finally, if the assets, liabilities and income are very complex, a deposition is essential to educate the lawyers.