The LGBT community may have a well placed suspicion when it comes to discussions of morality because the language of morality has so often been used to justify beating up on us.
A caricature of the divide: We actually do talk about morality. We often talk about it terms of consequences. In other words, we typically say, "Here's what will happen if you adopt this sort of legislation." And there are good reasons to do so when those consequences are people taking their own lives, dropping out of school, having poor health, experiencing unemployment and homelessness, and so on. We should never lose our ability to talk about the consequences whether we use statistics or stories. Both matter. Both communicate the problem.
Our opponents talk about consequences, too, though the consequences they talk about exist in the fantasy/nightmare realm and not in reality. They imagine all kinds of bizarre outcomes from sharing showers, bathrooms, and changing rooms with LGBT people. Those imaginations take particularly brutal turns when it comes to the transgender community as we have seen again and again. So our opponents talk about consequences, just not evidence based consequences.
The difference is that our opponents think they are also using the moral language of principle, though I don't think they actually succeed, whereas I think often our side doesn't do so. Sometimes our only principle seems to be "discrimination is wrong," which is true, as far as it goes. But there is more to say. So we could do more to shore up our side of the argument.
What we could be adding to our argument from a moral point of views?: We could spend more time asking and answering some of the basic questions of morality, which is not a mere list of rights and wrongs. The big questions of morality are issues like "What is the good life?" and "How do we know what's right or wrong?"
In the Western tradition, "Know thyself" has been at the heart of the quest for the moral life, even as Western society has failed miserably at operationalizing that quest. But it's still right idea. That maxim is particularly relevant to the set of issues in the transgender student bathroom bill debate.
Bringing the matter to the topic before us, we need to ask exactly how Rep. Susan Lynn knows who belongs in which restroom and what that has to do with her self-knowledge and the self-knowledge of transgender students. What are her methods really--inspection of a piece of paper, inspection of culturally derived gender stereotypes like clothing or hairstyle, inspection of body parts that she assumes correspond with only one gender but not any others? Take a minute to think through exactly how a regime could be put in place to enforce a rule that requires any of those three kinds of evidence to enter a restroom.
Moral knowledge is about guidelines we make or discover for ourselves and how we will interact with others based on what we know about ourselves. Moral rules are not guesses we make about others that are then imposed on them. Such guesswork precisely removes moral agency from others and becomes, by definition, immoral through the use of compulsion and arbitrary application.
Morality recognizes that each person is seeking and finding varying levels of self-knowledge. Morality recognizes that one will know more about oneself than others will. To bring that point back to the bill, no matter how smart and experienced Rep. Lynn may be, she actually can't know better than a transgender student which bathroom is best and safest and most fitting for a transgender student. And in the absence of bad outcomes resulting from those students making their own choices, they really ought to get to continue making those choices without the interference of state law and whatever bizarre enforcement mechanisms might come with such a law.
That is really why this bill opens a set of moral questions. So we need to be prepared to talk about them.