Does New Jersey use new spouse's income to determine child support?

Answer 1

According to the guidelines, no... at least, not directly. However, they're called guidelines rather than rules for a reason. Courts generally have a considerable degree of latitude to decide what's "fair." If the new spouse is filthy stinking rich, the court may find that it's appropriate for a higher percentage of the parent's income (or imputed income, if the parent stops working) to go towards child support.

An example may help:

John has a wife Marcia and a child. He works as unskilled labor and earns minimum wage. He divorces Marcia but his work situation does not change. His income is low, so the amount he can provide towards child support would be similarly low.

John then marries Paris. Paris has income of $100,000 per month. John no longer needs to work (Paris' income can easily support both of them), so he quits his job. The court will impute an income to John equivalent to what he could earn if he bothered to work (probably minimum wage, since that's what he was making before; it may be higher if John has qualifications to work at a better-paying job). They may also raise his child support payment to a much higher percentage of his imputed income... after all, if he wasn't being lazy and sponging off Paris, he could be working and giving all that income to the child (since he clearly doesn't need any of it).