Death row inmate Rodney Reed returned to a Bastrop County courtroom Tuesday morning for what his defense attorneys hope will be a chance to prove his innocence in the 1996 murder of Stacey Stites and get a new trial.

The person they say is responsible for the crime — Stites’ fiancé Jimmy Fennell — will not testify in court this week, visiting judge Doug Shaver declared at the start of the four-day hearing.

Fennell, whose alibi the night before Stites’ slaying is in question, submitted an affidavit to the court saying that if he were called to the stand, he would plead his Fifth amendment right not to testify and would not answer questions. His attorney said he would stand by the statements he made 20 years ago: that he was home with Stites the night before her death on April 23, 1996, before she went to work. She later was found raped and strangled on a rural road in Bastrop County.

"I will not answer the questions," Fennell said in the affidavit. "I will respond to each question that I am declining to answer the question based on my Fifth amendment right not to testify."

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Fennell would have been a key witness in the hearing.

The Texas Court of Criminal Appeals in May remanded Reed’s case back to Bastrop County to weigh claims that the state withheld critical evidence from the defense in the original trial, namely a CNN interview with Bastrop County sheriff’s deputy Curtis Davis, in which the law enforcement officer said Fennell told him that he had been out drinking the night before Stites’ murder and came home late, which conflicts with Fennell’s alibi.

Reed was convicted of capital murder in 1998 for Stites’ death. He has sat on death row for 20 years, maintaining his innocence. On Tuesday, he sat stoically in the courtroom in red prison stripes, flanked by his attorneys, who told the judge they have new evidence that points to Fennell as the killer, which they hope to present at the hearing this week, including testimony from a forensic pathologist.

The state said this evidence is outside the scope of the hearing and urged Shaver not to retry Reed’s case.

"There is absolutely no link between what we have, a supposed inconsistent statement, and a forensic pathologist," said Assistant Attorney General Matthew Ottoway. "That is the only thing we are here on, your honor, whether Jimmy Fennell supposedly was not where he says he was at. Forensic pathology has nothing to do with where Jimmy Fennell was or was not. It is not opening a retrial."

According to the defense, there are inconsistencies with Stites’ time of death. Attorney Bryce Benjet has said the state’s expert witness, then-Travis County Medical Examiner Dr. Roberto Bayardo, has disavowed his testimony at the original trial about Reed’s semen, which was found in Stites’ body. He had originally said it could have only come from a sexual assault at or near the time of her death.

FROM JUNE 2016: State court wants additional answers in Rodney Reed appeal

He later issued a declaration that it could have been deposited days earlier, firming up the defense’s theory that Reed and Stites were having an affair and had consensual sex before her death.

Benjet said the new evidence is critical to the lingering questions about Fennell that the appeals court asked Bastrop County to consider. Shaver has not decided whether to allow the testimony from the forensic pathologist at the hearing.

Ottoway requested that Davis take the stand first to answer questions about the CNN interview and Fennell’s whereabouts the night before Stites’ murder.