Walter Brennan did not receive an Oscar nomination for portraying Doc Velie in Bad Day At Black Rock.
Brennan plays the doctor of the secluded town with a secret and is one of the few decent men in the town. Brennan is probably best known for his more wily and colorful performances, but when he needed to give a more subtle performance he was more than able to dial down his more common on screen persona. That is the case here as Brennan gives a pretty quiet performance that very much fits the setting of the rather grim town where a horrible deed has take placed that wishes to be covered up by most of the populace, but wants to be dug up by the outsider Macreedy. Brennan is probably the brightest face in town, but to be honest Brennan is not exactly beaming either.
Brennan is very effective in his portrayal of the doctor finding the right tone of apathetic pessimism with only the slightest hint of optimism at the beginning of the film. It is very remarkable to see the usually cherry Brennan play a character who is depressed by his surroundings especially since Brennan handles the part so well. There is the idea of a once warm and caring man in Brennan portrayal of the doc, something that comes natural to Brennan's onscreen personality, but there is something quite powerful in the sad state Brennan shows the doc to be in. There is no sugar coating that Brennan gives any of his lines being quite blunt in his performance that effectively reinforces the tension of the film.
As the film progresses the doc slowly finds a greater courage to confront the town's past, and try his very best to help Macreedy. Brennan is very strong in the moment where the doc speaks his mind as he has the right convincing passion in the scenes. Brennan is excels in these moments not only in portraying the doc's conviction but showing just the right little bit of hesitation. The doc speaking out the way he is does makes it seem very likely that he will be killed along Macreedy and Brennan rightfully shows that the doc knows this. By suggesting this fear the doc's speech about no longer sitting idly by has the emotional punch it should, and actually makes another one of the conspirators breakdown believable.
Walter Brennan's performance stands out well in this fairly strong ensemble and he has a nice subtle chemistry with Spencer Tracy in their scenes together. They show an underlying understanding between two good men who have compromised more than their own moral compass will allow. He supports Tracy wonderfully and nicely adds to the power of the film thorough his somber portrayal of the doc. Brennan's work here is strong example of his talent and proves that he was as capable of a realistically drawn man like the doc here as he was in his performances as the colorful characters he is best known for.