WAYNESBURG, Pa. -- Greene County Assistant District Attorney Linda Chambers began her opening statement in the death penalty trial of Jeffrey R. Martin by projecting onto a screen a large photograph of 12-year-old rape and homicide victim Gabrielle Miranda Bechen.

"This is a picture of Gabby. I put her picture up because I want you to remember this is about her," Ms. Chambers told the jury in the county's first capital murder case in about 13 years.

The jury must decide whether Mr. Martin, 50, of New Geneva, Fayette County, a laborer on a horse farm not far from Gabby's home in Greensboro, raped and strangled her on June 13, 2006, and then buried her body, her ATV, her helmet and her shoes in four separate locations.

Gabby's disappearance precipitated an intense search of the remote area of Greene County by state police, the FBI and law enforcement authorities from Greene, Fayette and Washington counties and scores of volunteers -- including Mr. Martin, Ms. Chambers noted. When her ATV, a birthday present, was found four days after her disappearance, buried and covered by manure on the horse farm, suspicions surrounding Mr. Martin intensified.

On the fifth day, he confessed that he killed the girl, who often visited the horses and other animals on the farm. He said he did so because she had threatened to tell her parents that he had molested her -- an allegation Mr. Martin told state police was untrue.

Ms. Chambers told the jury Mr. Martin confessed to using a backhoe to dig a six-foot grave for Gabby's body, burying it there with 100 pounds of lime. He took police to that burial site and to the others for the helmet and tennis shoes.

"You're going to hear his [taped] confession," Ms. Chambers told the jurors. "You're going to hear the defendant's own words so he can tell you what he did ... [that] it took a while to kill her."

Ms. Chambers also said that forensic pathologist Dr. Cyril H. Wecht will testify about the autopsy that showed evidence that Gabby was raped, although Mr. Martin has denied that.

She also alluded to the "CSI effect," which causes jurors who watch that and other popular TV procedural shows to expect evidence like DNA to be at crime scenes. In this case, she said, a lab technician will explain why no DNA was present because of the effects being buried under dirt and lime for five days has on body fluids.

Ms. Chambers apologized for what she said will be graphic testimony and photographs that are necessary to help the prosecution prove its case.

In his opening statement, Public Defender Harry Cancelmi pleaded with the jury to keep an open mind in such a horrendous case.

"This is so rare, so abhorrent, so unheard of to us in Greene County there's a presumption that Mr. Martin did this," because he was arrested and charged, Mr. Cancelmi said. He pointed out that the prosecution has the burden of proof.

He urged jurors to look at the "voluntariness and value" of the confession, saying his client was kept in a hot police car without water for hours and was intensely questioned by "agitated" state troopers who berated him for wasting their time until he confessed.

He said his client may take the witness stand.