Laborer Convicted in Baby’s Death : Courts: A jury rejects the Huntington Beach man’s contention that he didn’t abuse his former girlfriend’s 14-month-old daughter, who was killed in 1990.

A Huntington Beach laborer was convicted Thursday of first-degree murder and sexual assault charges for the beating death of his former girlfriend’s 14-month-old daughter.

Wayne Yoshisato, who had maintained his innocence in the slaying, wept as the court clerk announced the verdict, his head in his hands. The 30-year-old man had been out on bail but was taken back into custody following the verdict, which came after nearly three days of deliberations by a Superior Court jury.

His family also wept in the courtroom as jurors found him guilty of murder, four counts of sexual assault and felony child endangerment.

With the conviction, Yoshisato faces a possible sentence of 25 years to life in state prison when he is sentenced Oct. 7, Deputy Dist. Atty. Carolyn Kirkwood said.

The prosecutor commended the jury for its work in the five-week trial, which at times contained graphic testimony of abuse and torture.

“It takes a lot of perseverance on their part,” Kirkwood said.

The child’s mother, Pepper Grunbaum, was not in court for the verdict but testified during the trial.

“It’s been a very painful experience for her, a very emotional experience for her,” Kirkwood said. “I just think she’s trying to get through it the best she can.”

Yoshisato’s lawyer, Deputy Public Defender Stephen J. Biskar, declined to comment after the trial.

Felicia Lynn Grunbaum was beaten to death July 10, 1990, in a Huntington Beach home where she lived with her mother, then 19, and Yoshisato.

The young mother and her child had moved in with Yoshisato, an unemployed laborer who raised dogs, shortly after Memorial Day that year in a “whirlwind relationship” that had started only weeks earlier, Kirkwood said.

In the 40 days the three lived together, Kirkwood alleged the child became a victim of an escalating pattern of abuse at the hands of Yoshisato.

“He’s upset with her crying,” the prosecutor said during her closing argument to the jury. “His temper flares. He hated her. He wanted to hurt her.”

But in his closing argument before the jury, Biskar said there were questions about who really abused the baby, suggesting it could have been the child’s mother.

“That’s what you have to decide,” he told the jury. “Who did it.”

If anything, Biskar contended his client’s only mistake was not acting to save the baby. “That’s what he has to live with for the rest of his life,” Biskar told the jury.

But jurors rejected that argument and found that the boyfriend was responsible.