Plaintiff sues following acquittal on murder charge; court finds probable cause and affirms summary judgment for defendants on malicious prosecution claim, but finds viable due process claim based on witness’s affidavit that officers induced him to identify plaintiff as guilty party, finds district court erred in concluding that affidavit was incredible as a matter of law; probable cause is not a defense to a due process claim based on fabrication of evidence; due process claim does not fail even though witness did not testify at plaintiff’s criminal trial: “Notwithstanding the nomencl