It's been more than two years since two Napa women were stabbed to death in the upstairs bedrooms of a west Napa home, and the court case against accused murderer Eric Copple is beginning to heat up.

The brutal stabbings of Adriane Insogna and Leslie Mazzara, both 26, in the early morning hours of Nov. 1, 2004, shocked and frightened Napa Valley residents. It took nearly a year, and a nationwide search for clues, before police made an arrest. On the night of Sept. 28, 2005, Eric Matthew Copple, 26, of Napa, accompanied by members of his family, turned himself into the Napa Police Department. Police say he confessed to killing the two women in their home on the 2600 block of Dorset Street.

Copple was arrested booked into the Napa County jail charged with two counts of murder and special allegations of use of a deadly weapon and multiple victims. He pleaded not guilty in October 2005.

Copple is scheduled to appear in court on Wednesday. At that time the Napa County District Attorney's Office may announce if prosecutors will seek the death penalty against Copple. If they do, they will have to prove at trial not only that Copple is guilty of murder, but that the crime involved a special circumstance -- in this case double murder or lying in wait for his victims -- that would qualify the crime for capital punishment.

If prosecutors were to seek the death penalty against Copple and prevail, he would be the only Napa County inmate assigned to California's death row. However, there have been cases where Napa prosecutors have sought the death penalty (see sidebar, "Napa's history with capital crimes," below).

Police say Copple waited outside the home for hours before entering, going upstairs, and killing the two women.

The motive for the double slayings has not been made public. Copple is the husband of Lily Prudhomme Copple, who was close friends with Insogna.

Lily Copple is employed at the Napa Sanitation District, where Insogna worked as an civil engineer.

Insogna's mother, Calistoga resident Arleen Allen, said her daughter also was friends with Eric Copple.

Although the case remained stagnant for almost a year, detectives actively pursued leads, tested the DNA of people known to the victims and conducted interviews. The break in the investigation came in late September 2005, when Napa police released new DNA findings.

DNA samples found on Camel Turkish Gold cigarettes matched that of blood found at the scene of the murder. Copple smoked that brand of cigarettes. Investigators said they believed Copple read or heard about the DNA findings, believed that police were closing in on him and turned himself in.

After he was arrested, detectives took a sample of Copple's DNA, which apparently matched the DNA found on the cigarette butts.

Mark Boessenecker, Napa County chief deputy district attorney, and deputy district attorney Rob Wade are prosecuting the case. Both have experience in murder cases. Boessenecker tried many such cases before shifting from the San Mateo County District Attorney's office to Napa. Wade wrapped up his most recent murder trial just weeks ago, earning a first-degree murder conviction against Napa dentist Michael Posey.

Copple is being represented by Napa County Public Defender Greg Galeste and Vallejo attorney Amy Morton.