SAN DIEGO — When the jurors who convicted David Westerfield return to court Wednesday, they will settle into the same pale blue chairs in the jury box, pick up the same pens and red stenopads and pass each other cups of water from the same pitcher they used during the guilt phase of the case.

But familiar surroundings aside, the penalty phase is a very different proceeding. Gone is the presumption of innocence that once cloaked Westerfield. Jurors now will decide what punishment he deserves for kidnapping and killing 7-year-old Danielle van Dam.

Over the course of several days, jurors will likely hear wrenching testimony in which witnesses offer memories, opinions and emotions inadmissible during regular trial testimony.

Prosecutor and defense lawyers will lay Westerfield's entire life before the jurors. Danielle's parents will not only testify about their daughter's life, but also are likely to describe the devastation caused by her death. And at the end, the panel must decide whether the 50-year-old design engineer deserves to die by lethal injection or to live in prison for the rest of his life.

Danielle van Dam

The six men and six women selected to hear the case last May are all death-qualified, meaning each said they could impose the death penalty if it was warranted. To determine which punishment is appropriate, jurors are instructed to weigh factors that aggravate Westerfield's guilt — such as previous convictions, prior violent behavior, and the heinousness of the murder — against factors that mitigate his guilt — such as any history of mental illness, childhood abuse or alcoholism.

If the aggravators outweigh the mitigators, the jury is to hand down a death sentence. If the factors are equal or the mitigators outweigh the aggravators, they are to impose a life sentence. Their decision must be unanimous. If they deadlock, the judge will dismiss the current jurors and impanel a brand new jury to rehear the penalty phase and decide on a sentence.

Prosecution's case for execution

At the top of the list of aggravating factors prosecutors can invoke is the crime at hand. Westerfield stole Danielle from her bed last February, murdered her and then dumped her body 25 miles away in a trash-strewn lot.

"The biggest thing the prosecution has is the body of the little girl found by the side of the road in the boondocks," said former public defender Curt Owen, who has tried three capital cases in San Diego County.

During his summation, prosecutor Jeff Dusek theorized that the gap-toothed 7-year-old spent her final hours in total terror, kidnapped by a man who was largely a stranger and then violently raped in his recreational vehicle. Her death, he told jurors, was not fast or quick, but torturous.

The van Dams are likely to testify about the effect the murder of their only daughter has had on their lives. During the trial, defense lawyer Steven Feldman cross-examined the parents about their risque sex practices and marijuana use, perhaps slightly tempering the emotional impact of their turn on the stand. But in the penalty phase, grilling the victim's grieving family is rarely done.

Prosecutors can also tell jurors about prior criminal behavior committed by Westerfield with certain restrictions. Past felony convictions are admissible, but Westerfield has a clean criminal record except for a drunken driving conviction.

The law, however, allows prosecutors to show evidence of uncharged violent crimes with the approval of the judge. If prosecutors know, for example, of accusations that Westerfield once molested a another child or assaulted a wife or girlfriend, even if the victim never contacted police at the time and the statute of limitations has run out, they can present evidence to the trial judge. During a hearing closed to the public, the judge can listen to witnesses, view evidence and hear the defense to determine whether to permit the jury to hear the allegations.

Judge William Mudd will hold a closed door hearing Friday and Monday to address this type of evidence.

If the judge allows testimony about alleged criminal activity before the jury, the panelists still have to determine for themselves whether prosecutors have proven these prior incidents beyond a reasonable doubt. Only then can they consider them as aggravating factors.

These type of criminal secrets — if they exist in Westerfield's past — would chip away at the image he had before the murder as an unremarkable suburbanite and "that could sway some of those jurors who have residual doubts about whether he did it," said Marjorie Cohn, an associate law professor at Thomas Jefferson School of Law in San Diego.

Prosecutors can also call experts to say that Westerfield will likely offend again if released. The life term does not envision release at any time, but the prosecution is permitted to tell the jury that a convict might be pardoned and freed by some governor at some future time and the only way to ensure community safety is death.

In his arguments to the jury, prosecutor Jeff Dusek will likely say that Westerfield as the killer of a child is "the worst of the worst" and only death is a proper punishment.

"What the prosecutor is trying to do is draw a circle of humanity and put [Westerfield] outside that circle, and what the defense is trying to do is bring them back in to the circle," said criminal defense lawyer Elizabeth Missakian, who has tried five capital cases in San Diego county.

Defense to argue life for Westerfield

Because of the severity of a death sentence, the law is extremely flexible on what evidence capital convicts like Westerfield can use during the penalty phase. Anything "which extenuates the gravity of the crime even though it is not a legal excuse for the crime" can come before the panel for consideration.

Westerfield's family, including his two teenage children, ex-wife, sister and mother, can all take the stand, describe the man they knew and essentially beg for his life.

During the trial, prosecutors said the "scariest part" of Danielle's murder was that the perpetrator was a "regular, normal guy" from down the street. The defense can portray the crime as an aberration in an otherwise normal life. They can tell jurors about the medical advancements his design engineering business made and the patents he registered.

His son, Neal, already testified about the apparently close relationship he had with his father, and the daughter of one of his former girlfriend's said that when she was caught in an abusive relationship, he opened his doors to her for three months. The defense can focus on such details, Owen said, to say, "This guy is just like you. He's not a monster."

The law also says that jurors can take into account whether the crime was committed when the defendant was too intoxicated "to appreciate the criminality of his conduct or to conform it to the requirements of the law." Westerfield's ex-girlfriend said she left him, in part, because of his drinking and bar patrons who saw him the night of the abduction said he was drinking, with one friend even calling him very drunk. The defense can call experts to explain how drinking affects behavior.

The defense can also play on any lingering doubts that jurors have. During the trial, Westerfield's defense relied heavily on insect experts who said bug evidence indicated Danielle might have been killed after Westerfield was under police surveillance.

With their verdict, jurors said they didn't think the bug testimony rose to the level of a reasonable doubt, but the defense could raise the entomological evidence again during the penalty phase and tell the jurors if they have any doubt, reasonable or not, a life sentence is more appropriate.