Who does Proctor bring him to court with him?

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In Act 3 he brings Mary Warren with him so that she can confess to not seeing spirits or seeing the devil which ultimatley defeats his goal when she turns on him after Abigail and the other girls pretend to see a 'bird' about to attack them in the courtroom. Mary Warren accuses Proctor of being in league with the devil and that he would wake her up in the middle of the night trying to get her sign the devils book which she ultimatley did.