The authors of the Declaration of Independence identified certain rights granted by our creator. These natural rights are inalienable--they can't be taken away by governments. Among them, the authors wrote, are life, liberty, and the pursuit of happiness. It's not an exhaustive list. The Supreme Court has expanded it to include the right to decide on the upbringing of our children, the right to marry the person of our choosing, and the right to make our own reproductive decisions.
Surely the right to know where you came from should fall within this list.
Adoptees made this argument in a 1979 New York court case,
Alma v. Mellon.* The federal Court of Appeals pooh-poohed the claim, contending the need to protect the adoptive family and the first mother's family trumped the adoptees' need to know their heritage. The judges made the patently absurd claim that mothers gave up their children on condition of anonymity. Does anyone believe that any first mother had a conversation which went like this: "If you don't guarantee me that my child will never, never, find me I'll just keep him?"