What is done in a CS case/modification where noncustodial parent is trying to reduce child support saying he doesn’t have a job but was fired for cause and has continuously lied about his income to the court to reduce child support calculation and has actually started his own business?
The court will look to all evidence, and you should make a case regarding his behavior. If the court finds he is intentionally and in bad faith suppressing his income to avoid paying spousal support, the court will impute income to him in the amount he is capable of earning.
If I have evidence that he lied about his income in 2001 when the child support was originally set and then lied about his income last year when a modification was done will the court award arrears.
There’s not much you can do about the 2001 income at this point. However, if you have new evidence that you can bring to the court’s attention and the modification has not occurred yet, you can bing all that evidence to light to show that he’s not being forthright about his current income. The court will take that into account in setting the appropriate amount of child support pursuant to the Guidelines.