An appeals court threw out a manslaughter conviction Wednesday against a man accused of literally scaring a woman to death when she had a heart attack after returning home to a burglary in progress.

The state 3rd Circuit Court of Appeal also went a step further and acquitted Willie James Robertson in the 1999 death of Irene Schoofs, 86, meaning prosecutors cannot bring him back to trial if the appeals decision is not successfully challenged by prosecutors.

Robertson, 47, was indicted on a second-degree murder charge in 2012 after cold-case investigators linked him to fingerprints collected more than a decade earlier at Schoofs’ Adrienne Street home.

Prosecutors argued Schoofs had a heart attack after returning home to find Robertson in her home; a jury convicted him last year on the lesser charge of manslaughter.

State District Judge Glennon Everett sentenced Robertson to the maximum possible sentence for that charge of 40 years in prison.

The fingerprints were the only evidence in the case and not enough to support the manslaughter conviction, a three-judge appeals panel ruled Wednesday.

The appeals decision noted 18 hours had passed from the time Schoofs is believed to have died until the discovery of her body and prosecutors did not offer evidence to rule out she could have died before Robertson allegedly broke into her home.

Schoofs was found lying on the floor of her kitchen, plastic grocery bags in her hand. Her wedding ring, a VCR and silverware were missing.

“It was speculated that the burglary was in commission at the time of the victim’s arrival (at home) since groceries were missing from the plastic bags and her wedding ring was gone from her finger,” the appeals judges wrote in a seven-page ruling. “However, the state failed to eliminate beyond a reasonable doubt the very real possibility that the victim was already deceased when the burglary commenced.”

Defense attorney Edward Marquet, who handled the case on appeal, said the story of a burglar scaring the woman to death might have made for a compelling story at trial, “but there was no evidence to prove that.”

Prosecutors could ask the state Supreme Court to review this week’s appeals decision.

The prosecutor in the case, Roger Hamilton, did not return a call to his office Wednesday for comment.

Marquet said he is working to secure the release of Robertson, who is being held in the Avoyelles Parish Correction Center.