A Cambridge University psychologist testifying in a federal trial on California’s same-sex marriage ban says children raised by same-sex parents are as well-adjusted as children raised by a mother and father.

Developmental psychologist Michael Lamb also said Friday that many children with two mothers or two fathers would thrive even more if their parents were able to get married.

Lamb’s testimony is being used in an attempt to undercut arguments by Proposition 8 sponsors that restricting marriage to a man and woman can be justified by the need to foster procreation and to make sure that children are raised by their biological parents.

Read the rest of Lisa Leff’s AP article here.