Is IRV constitutional?
Yes. There are no federal constitutional obstacles to IRV for any federal, state or local office. Indeed, IRV has been tested in courts on federal constitutional grounds, and been upheld. Nothing in the federal constitution specifies a particular voting method to be used for any office. Some state constitutions may have provisions that would need to be amended to apply IRV to certain offices. But even those states with constitutional mandates for plurality winning thresholds may not have constitutional barriers since a candidate with a majority after an IRV tally, in fact also has a plurality (more votes than any other candidate). There is a strong argument that an IRV statute structured such that an IRV process that automatically reduces the field to two finalists, declaring whichever of these two has the plurality at this final stage elected, would comply with such plurality state constitution language, though it has not yet been tested in court.
