The case hinges on the fact that no doctors were used for the artificial insemination. The state argues that because William Marotta didn't work through a clinic or doctor, as required by state law, he can be held responsible for about $6,000 that the child's biological mother received through public assistance _ as well as future child support.

Angela de Rocha, spokeswoman for the Kansas Department for Children and Families, said that when a single mother seeks benefits for a child, it's routine for the department to try to determine the child's paternity and require the father to make support payments to lessen the potential cost to taxpayers.

Marotta, a 46-year-old Topeka resident, answered an online ad in 2009 from a local couple, Angela Bauer and Jennifer Schreiner, who said they were seeking a sperm donor. After exchanging emails and meeting, the three signed an agreement relieving Marotta of any financial or paternal responsibility.

But instead of working with a doctor, Marotta agreed to drop off a container with his sperm at the couple's home and the women successfully handled the artificial insemination themselves. Schreiner become pregnant with a girl.

Late last year, after she and Bauer broke up, Schreiner received public assistance from the state to help care for the girl.

The Kansas Department for Children and Families filed a court petition against Marotta in October, asking that he be required to reimburse the state for the benefits and make future child support payments. Marotta is asking that the case be dismissed, arguing that he's not legally the child's father, only a sperm donor.

A hearing is set for Tuesday.

Marotta told The Topeka-Capital Journal that he is "a little scared about where this is going to go, primarily for financial reasons.'' His attorney didn't immediately return a phone message Wednesday from The Associated Press.

Court records show that Marotta, Schreiner and Bauer signed an agreement in March 2009, with the women agreeing to "hold him harmless'' financially. The agreement also said the child's birth certificate would not list a father.

But the state contends the agreement isn't valid because a doctor wasn't involved.

Under a 1994 Kansas law, a sperm donor isn't considered the father only when a donor provides sperm to a licensed physician for artificial insemination of a woman who isn't the donor's wife. The result is an incentive for donors and prospective mothers to work with a doctor, de Rocha said.

"I believe that is the intent of the law, so that we don't end up with these ambiguous situations,'' she told The Associated Press.

Also, the Kansas Supreme Court ruled in October 2007 that a sperm donor who works through a licensed physician can't legally be considered a child's father _ and doesn't have the right to visit the child or have a role in its upbringing _ absent a formal, written agreement. But the case involved a sperm donor who was seeking access to a child but had only an informal, unwritten agreement with the child's mother.

Linda Elrod, a law professor and director of Washburn University's Children and Family Law program, said the law seems clear: Sperm donors who don't want to be held liable for child support need to work with a doctor.