Retired Cleveland County Sheriff's Department investigator Cliff Winkler can't ever forget the images of finding 8-year-old Shane Coffman's badly decomposed body packed inside a deep freezer behind a Newalla trailer home on Feb. 9, 1996.

"It's a case that has really haunted me over the years and I feel like at least tomorrow, there will be some closure to it," Winkler said in a phone interview Wednesday morning.

He said 13 years have passed, but he remembers the events that unfolded that winter day as if it were yesterday.

"It was almost 5 o'clock when I got a call from headquarters that some people found what they thought might have been human remains in a deep freezer," he said. "I went out to the residence and looked in the deep freezer. I could see that it was what appeared to be a child, the bones of his little fingers were showing and just the top portion of his skull. It was very obvious it was a human and most likely a child."

Donald Gilson, the man convicted of killing Coffman, is scheduled to die by lethal injection 6 p.m. today at the Oklahoma State Penitentiary in McAlester, the same place where he has served prison time.

Last month, an effort was made to spare Gilson's life. The Oklahoma Pardon and Parole board met April 14 and recommended clemency for Gilson by a 3-2 vote.

Gov. Brad Henry granted Gilson a short execution stay in order to review the recommendation and other information related to the case. Henry decided Monday to deny Gilson clemency.

Winkler said he has no plans to travel to McAlester and witness Gilson's execution. However, he believes Gilson's death might bring closure to the case.

After Winkler found the remains in 1996, he said he immediately called his office for assistance, notified the Oklahoma State Medical Examiner's office and cordoned off the scene.

Winkler said the freezer was unplugged and filled with dirt. Shane's body had been stuffed inside the freezer almost six months before Winkler discovered him. Investigators believe Shane died around Aug. 17, 1995.

"Once the medical examiner came out and made his determination, I called the OSBI so we could use their laboratory people to process the freezer and any other evidence," he said.

Investigators found a pair of jeans and a shirt inside the freezer, but it was difficult to determine if Shane was clothed at the time of his death, Winkler said.

"When the medical examiner and OSBI started to move things, they couldn't tell," he said.

A medical examiner's report revealed Shane suffered acute fractures to his left jaw and right cheek in addition to a cracked upper incisor and fractures of the left collarbone, several ribs, a shoulder, a leg and his spine.

Winkler said detectives received consent from the trailer's owner to search the residence. That's when Winkler found a photo of Gilson, whom he recognized.