The other day I made this comment, which one reader asked me, very reasonably, to explain:
" I don't think people have a right to know who their fathers are, even if nearly everyone does, in fact, know."
A right is a serious thing. It is not just a wish. Moreover, I think that anything the state acknowledges as a right it must try to guarantee to the limits of its power.
I cannot think of a compelling state interest in ensuring that every citizen knows the identity of his or her biological father. That is what a right to know who your father is would entail. In particular, I cannot think of a state interest that would use the state's power to compel unwilling sperm donors to reveal their identities.
If the state, for some reason, knew the identity of your biological father and was withholding it, I agree that it is hard to think of why they should withhold it from you. That is not the same, though, as the state having an obligation to help you find out.
If not knowing who their biological fathers are causes donor-created children sufficient anxiety that they can convince the legislature to require all future donors to reveal their identity, that would seem to me to be a fair working of democracy. Future donors could then make a free choice to donate under those rules. Such a law, though, would not be reason enough to require past donors, who were assured of privacy under normal contract law, to be compelled to reveal their identities now.
I believe that many adopted and donor-produced children suffer real anxiety from not knowing much about their biological parents. It is such a problem that it might be worthwhile to require open adoption and open donation in the future. A more centrist, and likely, solution would be to create structures and incentives to help connect such children and parents. For example, it might be worth it to create registries of parents and children seeking one another, with a third party making the connections. It might even be worth it to create a government bureaucracy to seek out parents and children separated by adoption or donation secrecy, and ask them on behalf of the other party to reveal themselves. This could even be organized on a fee-for-service basis.
The larger issue is whether biological heritage is really the same as "identity" in the first place. As adoption has proven for centuries, social parents - the people who actually raise children - are real parents. They have a real and shaping effect on the identity of their children. I think this is even more true of donor-produced children, especially when raised by one of their natural parents. The fact that some - maybe most - children not raised by their natural parents are very curious about their natural parents does not mean that that knowledge is actually essential to the children's identity.