Heilman, Robert B. "The Criminal as Tragic Hero: Dramatic Methods."
Shakespeare Survey 19 (1966): 12-24.
Thesis: Heilman tackles a crucial problem in the understanding of Macbeth — our response to the hero of the play. If we distance ourselves from Macbeth and see his story simply as a tale of the defeat of a brutal tyrant, the play becomes moralistic rather than tragic. On the other hand, it's hard to sympathize with Macbeth, to see him as a traditional tragic hero—a good man who goes bad, eventually understands what has happened to him, and gains spiritual depth even as he dies.

We expect to identify with the tragic hero, but, Heilman writes, "when we share the point of view of Macbeth, we have to experience the deliberate choice of evil" (13). Furthermore, "we expect the tragic protagonist to be an expanding character, one who grows in awareness and spiritual largeness; yet Macbeth is to all intents a contracting character, who seems to discard large areas of consciousness as he goes, to shrink from a multilateral to unilateral being . . . . (13).

Macbeth kills his king, kills his best friend, kills an innocent woman and her children, and responds to the news of the death of his wife by commenting that he doesn't have time to grieve for her. How, Heilman asks, can we sympathize with such a man? Towards the end of his essay, Heilman summarizes his answer to this question:

My intention has been, not to offer a full study of Macbeth or a fresh account of his moral alteration, not to argue that he is a worse man than some have thought (though some analyses seem not to catch what Knights called 'the completeness [of] his final identification with evil') or a better man than other men have thought (though he is remarkably endowed with aspects of personality not ordinarily expected in a man committed to evil), but to describe the apparent impact made upon the imagination by certain deeds, thoughts, and feelings of his. Since there is hardly a need to demonstrate that Macbeth is a villain and that villains ordinarily repel us, the emphasis has naturally fallen upon those elements in him that tend to elicit, in whatever degree, fellow-feeling, pity, favour, or even admiration. Macbeth possibly establishes a subtle kinship by setting in motion certain impulses which we would rather not admit—anomalous siding with the criminal, aggressive ambition, envy, the pleasure of getting away with it (which includes leaving the 'it' unexamined). More frequently the appeal to allegiance is that of states or situations which are neutral in that they may come to good or bad men but which, without analysing the merits of the figure involved, we find it difficult not to fear or pity—the threat of exposure, the anxieties of a perilous position, relentless enclosure by men and circumstances, nightmares and insomnia of whatever origin, the pressing need for greater safety, the pain of miscalculation and the gnawing sense of a bad bargain, any enlargement of the penalties of advanced age, desertion, the unequal struggle, the role of the underdog. Finally, and more important, Macbeth early gives every sign of having a conscience, and later he exhibits qualities and abilities that normally elicit respect or admiration —resourcefulness under severely taxing stresses, readiness for intolerable difficulties, resolution, the philosophic cast of mind, endurance, bravery.  (20-21).
Still, Heilman is not satisfied with Macbeth:
Macbeth simply does not face the moral record. Instead he is the saddened and later bereaved husband, the man deprived of friends and future, the thinker, the pathetic believer in immunity, the fighter. These roles are a way of pushing the past aside — the past which cries out for a new sense, in him, of what it has been. If, then, our hypothesis about the nature of tragic participation is valid, the reader ends his life with and in Macbeth in a way that demands too little of him. He experiences forlornness and desolation and even a kind of substitute triumph — anything but the soul's reckoning which is a severer trial than the world's judgment. He is not initiated into a true spaciousness of character, but follows, in Macbeth, the movement of what I have called a contracting personality. This is not the best that tragedy can offer.  (23)
Note: This is an excellent essay, but it's not for beginners. In order to follow the argument you need a fairly detailed knowledge of the play.

Bottom Line: Very persuasive.