when six unelected justices
Sorry, but election is not a cure-all for all ailments. If it were, we'd have a pure democracy ("The People..." "lured by the loudest throat" -- Kipling).
I believe that the author was referring to a state of accountability to the electorate rather than the mode of selection. Lifetime appointments without feasible means of removal have no place in a republic and may be the greatest error of our nation's founders in designing our governmental system.