A court has ruled that a man who donated sperm to a lesbian couple in Kansas is the “legal father” of the child, and must pay child support.

William Marotta responded to an advert from the couple on the website Craigslist, donating a plastic cup of sperm and signing a contract waiving his parental rights.

However, the Shawnee County District Court ruled yesterday that he is legally the father of Jennifer Schreiner and Angela Bauer’s now-four year old daughter, as the couple did not involve a licensed physician in the insemination process.

The state was seeking to make Mr Marotta pay for $6,000 (£3,100) in public assistance that the mother had received, as well as to make him liable for future child support payments.

As Kansas does not give same-sex couples parental rights or allow them to marry, Ms Bauer was never recognised as the child’s mother, which her partner gave birth to in 2009.

When the couple split up, the Kansas Department of Children and Families instead sought out the biological father of the child, Mr Marotta, for child support.

In her ruling, Judge Mary Mattivi wrote: “In this case, quite simply, the parties failed to conform to the statutory requirements of the Kansas Parentage Act in not enlisting a licensed physician at some point in the artificial insemination process, and the parties’ self-designation of (Marotta) as a sperm donor is insufficient to relieve (Marotta) of parental rights and responsibilities.”

Kansas congressional representative Tim Huelskamp stated his opposition to equal marriage in February last year, claiming that ‘70% of Americans’ are against allowing same-sex couples to marry.