TBC: It is interesting to note that the term "Heresy-hunter" is hardly new, as this excerpt from an essay of 1910 notes.
Some people have very confused ideas about hunting for heresy, and about Christian liberty. If a man advances and seeks to propagate teaching which I regard as very injurious, if not ruinous, and I assail it with vigor, such vigor as he feels unable to resist on the merits of the question, it is common for him and his friends to cry out, "Heresy-hunter! Heresy-hunter!" If a lot of us should go prying into some man's utterances to find something wrong, somewhat as [some] hounds kept up a yelping all night . . . we might be charged with hunting for heresy; but if those hounds had seen a fox coming out of some man's hen-roost, nobody would have objected to their giving him chase. The fox might cry out for personal liberty, and say, "I have just as good a right to take a chicken as you have to take a fox," nevertheless, the common judgment of mankind would say that to chase the fox away would be a righteous act. Out West there are bear-hunters. They go creeping around among the hills and rocks trying to slip up on a bear and take the advantage of him. In this they are like real heresy-hunters. But if a man is walking along the public road, and meets a bear reared on his hind legs, and reaching for him with his fore paws, there is bound to be a fight or a foot-race; and if the man should fight the bear, nobody could on this account call him a bear-hunter. The bear might say, "I am free, and have as much right on this road as you have," and the man could answer, "I am free, too, and have as much right on this road as you have." And if the man should also say, "You are after hugging me, and you hug everybody you can get hold of, so I will put a bullet through you," the average citizen would say that the man was in the right. So, if heresy does not want to be shot at, it should play sly and not walk out into the public road (J. W. McGarvey, "Short Essays in Biblical Criticism," 1910, pp. 383-384)