Generally speaking, in order to modify child support, the party seeking the modification has to show that there has been a "material change of circumstances" since the most recent order. Common examples of "material change" include: changes in income of the parties; a child's age; a child's needs; the cost of living, etc. Keep in mind the court has broad discretion when it comes to modifying child support and support is always modifiable as long as the duty of support exists.
If my spouse gets remarried, will his/her spouse's income constitute changed circumstances?
A subsequent remarriage does not in itself constitute a change of circumstances, and, except in an extraordinary case, income of a parent's subsequent spouse or non marital partner may not be considered in child support determinations.
Will the parties have to exchange financial information again when requesting a modification?
Yes. If you request a modification or respond to your ex-spouse's modification request, you will have to submit an Income and Expense Declaration with copies of your two most recent pay-stubs. The parties will use this exchange of financial information to calculate state guideline support, also known commonly as "Dissomaster."
What if I feel my spouse is not being forthright in his/her financial disclosures?
It is important that parties reveal their true income and be forthright, after all the Income and Expense declaration is signed under penalty of perjury. However, if you are certain that your spouse is hiding income, there are tools you can use, such as a deposition subpoena to request records from your former spouse's employer; form interrogatories to illicit general information including tax returns; a deposition so your attorney can ask your spouse about all his/her income under penalty of perjury and more.