Can Parliament legalize samesex marriage? Can Quebec unilaterally secede from Canada? Can the federal government create a national firearms registry? Each of these questions is contentious and deeply political, and each was addressed by a court in a reference case, not by elected policy makers. Reference cases allow governments to obtain an advisory opinion from a court without a live dispute or opposing litigants – and governments often wield this power strategically. The first study of its kind, Seeking the Court's Advice draws on over two hundred reference cases from 1875 to 2017 to show that the actual outcome of a reference case – win or lose – is often secondary to the political benefits that can be attained from relying on courts through the reference power.