DNA found at the crime scene links a man to the slaying of his girlfriend's mother in La Mesa 25 years ago, a prosecutor said Monday in El Cajon Superior Court, but a defense attorney said the evidence was contaminated.
Marc Jernigan faces 26 years to life behind bars if convicted of stabbing June George 78 times in her kitchen on Aug. 8, 1986.
Deputy District Attorney Jill Schall said in her opening statement that the victim's then-19-year-old daughter, Kathy Keller, had dated Jernigan since high school, but they broke up a week before the killing.
Keller was in the process of closing a joint account with the defendant and opening one with her mother, the prosecutor said.
Jernigan, who wasn't working and lived with his mother about five miles away, was a frequent visitor to George's home and knew her habits and where she kept the spare house key, Schall said.
George was killed as she arrived home after running some errands and grabbing a salad to go, according to the prosecutor. The 47-year-old victim suffered stab wounds to her torso, back and neck, and the tip of a knife broke off in her skull, Schall told the jury.
Jernigan, now 44, was interviewed the night of the slaying but said he was home watching television and doing laundry, the prosecutor said.
At the time, Keller described Jernigan as "All-American" and "perfect" and couldn't imagine him killing her mother, Schall told the jury.
The case went cold until 2000, when La Mesa police reopened the case and performed more DNA testing, the prosecutor said.
Schall said the victim's wallet had been removed from her purse. Both were found at the foot of the bed, and blood stains taken from the wallet and bedspread belonged to the defendant, the prosecutor said.
Defense attorney Christopher Plourd told the jury that Jernigan's DNA was found in the victim's home because he was over there having sex with Keller all the time.
Plourd said Jernigan's DNA was not on the victim's body, however.
"We don't know who killed June George," the defense attorney said. "We do know it was not Marc Jernigan."
Jernigan and Keller's sexual relationship continued after George's death, and the defendant had no motive to kill her, Plourd said. In fact, he got along with George beautifully, the lawyer said.
He alleged that Keller was a drug user, unbeknownst to his client, and had a group of friends apart from Jernigan. The attorney said his client gave an interview to police the night of the murder, telling investigators he didn't know anyone who would want to do harm to George.
Officers at the crime scene searched for a weapon but couldn't find one, Plourd said.
The knife was found days later hidden in a drawer, meaning the weapon had to be in the possession of someone other than Jernigan, Plourd said.
He said there were problems with the evidence, alleging DNA samples were contaminated and mixed up, and told jurors that a DNA analyst who worked on the Jernigan case failed a proficiency test and was suspended.
"Marc Jernigan did not kill June George, and the DNA tells you that," Plourd told the jury.
City News Service contributed to this report.