What are the principles of a motion for a new trial where a witness in a murder trial later dies before the trial has even begun?

The foregoing principles were applied to a case with facts similar to the matter herein in (State v. Bunyan (1998) 154 N.J. 261, 712 A.2d 1091.) In Bunyan, the defendant, convicted of murder, had sought to introduce the exculpatory hearsay statement of a witness who later died. The witness, shown a photograph of Bunyan out of court, told an investigator that he was not the killer. The witness refused to execute a written statement before dying. Moving for a new trial, Bunyan sought to introduce the investigator's affidavit memorializing his conversation with the witness.