This is a common scenario - you are seeking a court order for child support, but the non-custodial parent is claiming an annual income far less than you suspect he/she actually earns.
One way to prove that a party’s actual income is higher than his/her reported income is to illustrate how his/her reported lifestyle could not be supported by the reported income.
The Appellate Division in Strella v. Ferro ruled that: in calculating a party's child support obligation, the court "need not rely upon the party's own account of his or her finances, but may impute income based upon the party's past income or demonstrated earning potential.”
In that case, the father claimed that he had been unemployed and only recently begun to earn $500 per week despite having recently earned as much as $101,000 per year. The Court imputed an income of $96,000 to the father. In doing so, the Appellate Court noted that:
Clearly, in the absence of incurring debt or drawing down on savings, if the party’s expenses exceed his/her reported income, then the reported income must be under-reported. In such a case, the Court should look beyond the filed tax return to calculate the child support obligation