In chapter 25 of To Kill a Mockingbird, why was Tom "a dead man the minute Mayella Ewell opened her mouth and screamed"?
Tom Robinson was considered dead as soon as Mayella screamed simply because he was black and she was white. During that time period in the South, no one would have believed a black person over a white person regardless of the situation. Blacks were considered guilty if accused by a white before even getting a chance to prove their innocence. Atticus was an excellent lawyer and he proved Tom's innocence to everyone in the courtroom, but 'in the secret courts of men's hearts' everyone had already convicted Tom without a trial.
Tom is a "dead man" because a white woman is accusing him of rape. In Tom's era (1930s) such a thing was an automatic death sentence. A "fair trial" as you will see, cannot be had and Tom does indeed die at the hands of those who are unwilling to believe in a black man's innocence.
Tom's guilty based solely on the color of his skin vs. the color of Mayella's skin. The simple act of being in the house alone with Mayella contributes to Tom's assumed guilt. Once Mayella screams, Tom is automatically considered guilty because she is white and Tom is black.
The vast majority of white people would never dare to believe- or at least admit to believing Tom’s version of what had really happened. Mayella had a strong advantage purely by the fact that she was white and not a Negro. During the 1930's in the South, no one would have ever dared to believed a black person over a white person regardless of the accused crime.
Tom was considered a dead man at that moment because he was a black man. In that time in Maycomb the people had a mentallity to "preserve". this was done by the way they had treated blacks. Even though all the evidence showed that he was innocent it didn't matter to the jury because he was a black man. basically it was a WHITE woman's word against a black mans which would be impossible for him to be innocent. He was of course sentenced to the "chair"(electricuted)