You can also find psychiatrists who call homosexuality a mental disorder. What's your point?
The point is I don't like giving the government the power to take away the rights of an entire class of people because I don't like what individual members do.
If we declaring entire groups of people unfit to adopt, the next things they go after will be things like "gun in the home," whatever they deem "racist" and "homophobia."
You do realize we have things like speech codes, sensitivity re-education and hate crimes laws because liberals took the conservative mantra of "legislating morality" and ran with it?