Certainly, one piece of evidence that would assist Proctor would be if Abigail and the girls were being cross examined properly and effectively. Part of what makes Proctor's claims so difficult for the people of Salem to accept is that Abigail and the girls' claims are taken with so much absolute certainty. There is little doubting or skepticism, which gives them unfettered power, thereby making Proctor's job difficult. Another piece of evidence that Proctor could use would have been Mary Warren's confession. Proctor's claims are validated if she does not wilt under the pressure of the trial and the peer pressure that Abigail and the other girls exert on her. Finally, I think that Proctor would have benefited greatly had Francis Nurse's petition been heard. Had the document been accepted, Proctor could have been able to use this as leverage, discrediting the accusations by testifying to Rebecca Nurse's sense of character. This would have helped to delegitimize the girls' claims and their intended victims. These would have helped Proctor make an evidential case to discredit the girls' accusations.