Four years ago, a couple named Samuel and Michelle Sweat divorced in Atkinson County after 14 years of marriage.

Now, the battle over who should pay what to support their three children could upend how child support is figured in Georgia, in a case critics say could help rich men and hurt poor children, and supporters say would make child support equitable for the first time.

The state Supreme Court heard arguments Monday on whether Superior Court Judge C. Dane Perkins was right to declare Georgia's child support unconstitutional last year when he ruled that Michelle Sweat need not pay child support.

Perkins' February 2002 ruling said Georgia's method of determining child support was unconstitutional because it unfairly penalized one gender -- men -- and violated due process. Georgia law bases child support on a percentage of a noncustodial parent's gross income, up to $75,000. with some exceptions.

Unlike Michelle Sweat, he wrote, most noncustodial parents are men.

The case has become a rallying cry for those trying to make Georgia's child support laws more lenient on noncustodial parents, who are also trying to change the law in the legislature.

Assistant Attorney General Nina Edwin urged the court to overturn the lower court ruling, saying Georgia's child support system would be thrown into chaos otherwise.

Michelle Sweat's lawyer, Daryl LeCroy, asked the court to not only uphold the lower court ruling, but take action itself to create a new and more equitable set of guidelines.

"This issue is too important to leave to the politicians," he said. "I urge you to act."

The Sweat case began in 2000, after Samuel Sweat asked the state to help him get child support from his ex-wife because she had reneged on an earlier agreement to pay for their children's insurance, Edwin told the court.

Edwin argued that Perkins overstepped his bounds in throwing out the law because he could have easily exempted Michelle Sweat from paying under the current law.

Both the judicial and the two pending legislative efforts are based on an analysis by Griffin consultant R. Mark Rogers, who markets a new way to figure child support, called CostShares, around the country, and advises parents trying to fight child support claims.

His model tends to shift more of the burden from noncustodial parents to custodial parents by counting both incomes, factoring in new children in the noncustodial parent's new family, tax credits and other benefits and costs.

According to one observer at Monday's arguments, Gwinnett County father William Webb, that's "only fair. Both parents should pay."

CostShares also exempts very low-income noncustodial parents from child support -- another boon, said Webb, who said he has been jailed several times since his sagging income left him unable to keep up.

The current law, created in the 1980s, functions as "hidden alimony" in higher-income cases, giving custodial parents more than a child costs and does not take into account second families, critics say.

"My children deserve equal protection," said Julie Batson, a second wife and president of Georgians for Child Support, which supports the Sweat decision. "I want my kids to count."

Adopting rules based on CostShares could reduce her family's child support obligation by more than one third, she said.

CostShares also sets a cap on the cost of raising children, based on the parent's income: At the top of the scale, a child whose parents earn a total of $96,000 per year would get no more than $949 monthly, according to a Senate bill. Currently, a noncustodial parent earning $75,000 would pay about $1,500.

CostShares' Rogers conceded that his formula could result in less money for children, and less for very poor children in particular -- although he blamed the latter on the state's welfare system: "That's the big public policy issue, which this state is trying to pretend doesn't exist."

He said the current formulas drive low-income parents into the underground economy, or into jail: "You can't squeeze blood out of a turnip, even if it's a very nice turnip," he said.

Rogers' proposal outrages Georgia Legal Services, which filed a friend of the court brief in the Sweat case and which represents largely custodial, low-income parents.

The proposed new guidelines would exempt poor fathers from paying child support at an income level far exceeding what poor mothers get from welfare, the agency contends. "There are many issues facing this state," said Vickie Kimbrell, an agency lawyer. "Children getting too much child support is not one of them."