A SURROGATE who gave birth to twins must remain registered as their mother on their birth certificates, it was argued in the Supreme Court.
Senior counsel Michael McDowell, pictured, argued there will be "massive" and "radical" consequences for the State if this is changed.
The State's position is that a woman who gives birth to a child is the mother of that child. Motherhood is a matter of fact and it cannot in law be based on genetics, he said.
Mr McDowell was opening the State's appeal before a seven-judge Supreme Court against a High Court decision last May that the genetic parents are entitled to be registered as the twins' parents on their birth certificates.
The twins were born to a surrogate, a sister of their genetic mother, some years ago.
Mr McDowell said it would be a matter of "grave public concern" with consequences for citizenship, succession and the criminal law, if the Supreme Court does not overturn the High Court decision.
The High Court had no jurisdiction to reverse the meaning of motherhood – and it was "radically wrong" in finding motherhood was based on genetics, he said.
If the genetic parents succeed, it would "put in complete doubt" the position of many women who now think they are mothers after giving birth to children themselves using eggs donated by other women.
New laws being introduced by the Oireachtas will address the position of the couple – but it is up to the State, not the courts, to legislate for these issues, he added.
The High Court found the State unlawfully discriminated between the genetic parents by permitting the genetic father to be registered on the birth certificate but not the mother, he said.
While scientific possibilities had changed, the law had not moved with them and any change now should be left to the Oireachtas.
As of now, the State's position was a child "cannot have two mothers at the same time".
The appeal, which is expected to last three days, addresses a range of complex issues when children are born as a result of surrogacy arrangements.
Earlier, the court ruled, given new laws concerning reporting of family law cases, the case may be reported on the basis nothing is published or broadcast that tends to identify the parties.