But that doesn’t mean that conduct that marginalizes the legislative branch is absolved of judicial review. In one notable case, Wisconsin Senator Ron Johnson is suing the White House over the ObamaCare regulatory carve-out that conjured up special subsidies for Members and staffers who were supposed to give up federal employee health benefits to join the insurance exchanges.

Mr. Johnson argues that because Members must designate which staffers do and don’t participate, the rule imposes a nontrivial administrative burden—i.e., he has standing to sue because the rule harms his office, not because he is a U.S. Senator. More to the point, Mr. Johnson claims that the rule forces him to become personally complicit in law breaking and thus damages his political reputation. Several appeals court precedents hold that elected officials who must maintain the public trust suffer injuries when their credibility is undermined, including a 1993 D.C. Circuit ruling by now-Justice Ruth Bader Ginsburg.

The White House claims Mr. Johnson lacks standing, but that’s because the lawyers don’t want to get near the merits. The real import of his lawsuit is that it invites the courts to restore the proper separation of powers amid executive encroachment.