Most contentious issues--marriage laws, universal healthcare, minimum wage, etc--are explicitly framed and argued (by both sides) with the language of justice. Moral preferences guide law; reason is just post-hoc rationalization.
You might object that "law" is not the same as "contentious issues," but that changes nothing. The emotionally charged political process that drives these debates is the same one that produces legislation. It is almost structurally incapable of producing rational outcomes.
Justice is not necessarily a moral concept, it's quite a reasonable concept as well. Laws are about reason in the sense that they're things we can convince majorities to abide by; sometimes those justifications are moral, but being immoral is not a justification to be illegal as morals themselves are fluid and what is moral for one isn't for another. As there are no absolute morals, laws are thus based on reasoning between moral beings as to what they can agree to.
Most contentious issues--marriage laws, universal healthcare, minimum wage, etc--are explicitly framed and argued (by both sides) with the language of justice. Moral preferences guide law; reason is just post-hoc rationalization.
You might object that "law" is not the same as "contentious issues," but that changes nothing. The emotionally charged political process that drives these debates is the same one that produces legislation. It is almost structurally incapable of producing rational outcomes.