An appellate court on Friday upheld the murder verdict of a man convicted of bludgeoning his elderly mother on Christmas Eve three years ago in their Town of Tonawanda house.

A jury two years ago convicted David C. Heck of second-degree murder for killing Ruth Heck, 87, in their home at 171 Conant Drive.

Heck challenged the weight and sufficiency of the evidence against him.

“The proof of defendant’s guilt is not only legally sufficient to convict, it is also fairly characterized as overwhelming," according to the unanimous ruling by the Appellate Division in Rochester.

Heck had slashed his left wrist after spending more than five days alone in the home with his mother’s body. He called 911 but could not speak into the phone. Authorities traced the call to his home.

Police found him in his second-floor bedroom. Police found his mother’s body on the living room floor, her head crushed by blows from a blunt murder weapon that was never recovered.

The appellate court said the evidence at the trial before State Supreme Court Justice M. William Boller established Heck “failed to notify police of his mother’s death for several days; falsely stated to his neighbors that she was alive despite his knowledge of her death; staged the crime scene to make it appear that his mother had accidentally fallen and hit her head and then proceeded to tailor his account of her death accordingly.”

Also, appeals judges cited evidence that Heck admitted to a fellow jail inmate while awaiting trial that he had killed his mother with a hammer.

A hammer was missing from the otherwise well-stocked toolbox, the appellate court said.

“Forensic evidence conclusively established that the victim did not die from a fall, as defendant had originally claimed, but rather from 13 blows to her head,” according to the appellate court.

Heck, 58, is being held at a state prison in Elmira serving a 25-years-to-life term.

During the trial, prosecutor Christopher J. Belling told jurors that Heck, knowing he and his mother were about to lose the home through tax foreclosure, concluded it was best to kill his mother and then himself.

Heck had lived for years off his mother’s Social Security checks.

During the trial, defense attorney John R. Nuchereno described the police investigation as incomplete and said they failed to conduct a search for an intruder.

Heck’s defense that an unknown intruder had killed his mother while he was out shopping “was unsupported by any credible evidence,” the appellate court said.

Heck “was the only person who had lawful access to the house apart from his mother, and there was no evidence that the house had been broken into or that anything had been stolen from it,” according to the appellate court. “Moreover, the fact that the victim was struck 13 times in the head is consistent with the (prosecution’s) theory that this was a crime of passion and not, as defense counsel suggested, the act of an intruder who unexpectedly encountered the occupant of a house in the course of a burglary.”

While the prosecutor’s comments denigrating the defense theory were indeed improper, “they were not so pervasive or egregious as to deprive [the] defendant of a fair trial,” the appellate court said.