ancient document best evidence rule burden of proof business records exception chain of custody character evidence circumstantial evidence cognition common law contract court crime criminal law cross-examination dead man statute declarations against interest defendant demonstrative evidence digital evidence direct examination documentary evidence dying declaration excited utterance exculpatory evidence expert witness eyewitness identification eyewitness memory eyewitness testimony habit evidence hearsay in english law hearsay in united states law implied assertion judge judicial notice jurisdiction lawyer learned treatise martyr memory oath party admission perjury physical evidence plaintiff present sense impression property law real evidence recorded recollection res gestae self-authenticating document sense similar fact evidence subpoena subsequent remedial measure testimony tort trusts and estates weapon focus witness impeachment witness protection