The jury’s decision to convict Tom Robinson for a crime he clearly did not commit plagues Jem (and many readers) as an intolerable miscarriage of justice. The most obvious reason justice isn’t served is because the jury’s overwhelming racism prevents Tom from getting a fair trial. Another reason the jury finds Tom guilty is because both Mayella Ewell and her father, Bob, both perjured themselves on the stand. In addition to the presumption of an impartial jury, the justice system operates on the assumption that witnesses will tell “the truth, the whole truth, and nothing but the truth” after being sworn in to testimony. But both Mayella and Bob lied rather than admit that Mayella tried to kiss Tom. Tom’s race, combined with the Ewells’ lies, proved enough for the racist jury to find Tom guilty, even in the face of overwhelming evidence of Tom’s innocence.