How can a father get out of paying more child support than he already does?

Answer 1

The obligated parent must petition the court to have the terms of the current child support order amended/rescinded. He or she will be required to submit valid documentation that the current amount is creating an 'undue hardship" for said parent. Undue hardship is defined in various ways depending (terminal/debillitating illnesses resulting in medical expenses, loss of employment, drastic reduction in salary and so forth.

Answer 2

In the United States every state is required by federal law to have child support guidelines and require that every child support obligor pay the required amount. It is not negotiable. A person would need a good reason not to pay (such as illness, inability to work, disability, etc.) and the case would be decided by a judge.