Why do the animals confess to being traitors?

While Orwell doesn’t explain why the animals confess to crimes they didn’t commit, readers can infer that the four pigs who are the first to be executed are terrified of the dogs and believe that if they do as Napoleon asks, he will spare their lives—after all, the Commandments stipulate that no animal should harm another. More puzzling might be the hens and the sheep’s confessions since they have seen exactly how Napoleon treats so-called traitors. However, the hens are among the least intelligent animals, so they may lack capacity to process the events. Similarly, the sheep have already proved themselves to be followers with little ability to think or question for themselves.