Jurors won't be allowed to consider sympathy for Scott Peterson's family when they decide if he should receive the death penalty.
Defense lawyer Mark Geragos argued that jury instructions should allow panelists to consider the affect a death sentence would have on Peterson's family, given that the fetus was to be a grandson to both the victim's and the defendant's parents.
But Judge Alfred A. Delucchi declined to include the clause in jury instructions.
"Sympathy for the defendant's family is not a matter the jury can consider in a capital case," he said Tuesday.
He also said he would tell jurors they could give Peterson a lesser sentence if they have doubt about the circumstances of the crime and its premeditation.
That means panelists could legally give Peterson life in prison without parole.
Defense attorneys have called 34 witnesses in the penalty phase of Peterson's murder trial and four or five witnesses were set to testify Wednesday. Delucchi told jurors to expect closing arguments after that and to begin deliberations Thursday.
Testimony on Tuesday turned to memories of the slain 27-year-old schoolteacher, bringing her mother to tears in the gallery.
An agriculture professor who taught both Scott and Laci Peterson while the couple attended California Polytechnic State University said Scott Peterson graduated with a 3.38 GPA and was on the dean's list three times.
"He was very intelligent, bright, confident, able, productive. He seemed more mature at the time ... like he was well-raised and well-rounded, the kind of student that sticks out," said Robert Thompson, Jr.
Prosecutors then questioned Thompson, asking how Laci's murder affected him.
"I've been grieving ever since," Thompson said, choking back tears. "I was close to Laci and she was such a warm .... type of person so I miss her terribly."
Sharon Rocha, Laci's mother, began to weep.
Scott Peterson was convicted Nov. 12 of one count of first-degree murder in the death of his pregnant wife, Laci, and one count of second-degree murder for the killing of her fetus.
Prosecutors say he killed Laci in their Modesto home on or around Christmas Eve 2002, then dumped her body into San Francisco Bay. The remains of Laci and the fetus were discovered about four months later a few miles from where Peterson claims to have been fishing alone the day his wife vanished.