Scott Peterson's attorneys claimed in court documents filed Friday that part of California's wiretap law violates the state constitution.
The challenge appears to be the second strike in trying to get wiretap evidence thrown out in the Peterson double-murder case.
Also Friday, attorneys for television networks filed more than 900 pages of documents outlining opposition to keeping the press and public out of Peterson's preliminary hearing, scheduled Sept. 9 before Stanislaus County Superior Court Judge Al Girolami.
A coalition of newspapers, including The Bee, already has asked Girolami to keep the hearing open.
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Peterson wants the hearing closed, arguing through his attorneys that widespread media coverage would jeopardize his right to a fair trial.
The 30-year-old fertilizer salesman from Modesto is charged with two counts of murder in the death of his wife, Laci, 27, and the couple's unborn son, Conner. He could receive the death penalty if convicted on both counts.
During the investigation into Peterson's disappearance and slaying, law enforcement intercepted hundreds of calls, including portions of calls between Peterson and his attorney and an investigator working for the defense team, court documents show.
Most information sealed
Little is known publicly about the substance of the conversations.
In the face of massive media attention, Girolami sealed most of the information in the case, including the wiretap recordings, autopsy reports and arrest warrant documents.
Court documents show that a judge approved a wiretap on Peterson's cellular phone on Jan. 10. That was 17 days after his wife's family reported her missing on Christmas Eve. The tap ended Feb. 4, according to notices sent to people whose calls were intercepted. A second wiretap ran from April 15 to 18, the day of Peterson's arrest.
Prosecutors who oversaw the wiretaps maintain that investigators carefully followed the law when intercepting and monitoring calls. But the newly filed defense documents question the legality of the law on which prosecutors relied.
Under one provision of the law on wiretaps, law enforcement officers must stop listening to calls that are of a "privileged nature." But they can spot-check those calls for up to 30 seconds every two minutes.
Co-defense counsel Kirk McAllister argued in Friday's filing that that section of the law is unconstitutional because it allows investigators to listen to attorney-client communication, which are specifically protected by state statute.
The wiretap law also gives law enforcement powers that are legally designated for judges, McAllister contends.
"(The law) is doubly defective," he wrote. "First, it allows law enforcement authorities to listen in on privileged conversation. Second, it empowers a police officer to decide what is privileged and what is not."
By doing so, it violates the state constitution's separation of powers provision, the defense contends.
The state constitution outlines three branches of government: legislative, executive and judicial. No one given power in one branch may exercise power in another, unless expressly provided for in the constitution.
Since police are officers of the executive branch, they cannot also function as members of the judicial branch, legal observers said.
"Beyond a doubt, giving police officers too much power without the check of the judiciary violates the separation of powers," said Diane Amann, professor of constitutional law and criminal procedure at the University of California at Davis. "It's an open question, within California, whether these provisions cross that line."
In a previous challenge to the wiretaps, the defense alleged "grave prosecutorial misconduct" as a result of investigators monitoring calls between Peterson and his defense team.
The defense has asked the judge for a range of sanctions that include keeping the calls from the trial and having Stanislaus County prosecutors removed from the case. Girolami is to hear arguments on the issue the same day as the preliminary hearing.
Several legal observers said the latest defense approach keys on what appears to be an untested area of the law.
Regardless of how Girolami rules, the issue is likely to be appealed to a higher court at some point, said Ruth Jones, a former prosecutor who now teaches criminal law at McGeorge School of Law in Sacramento.
"It would be very unusual for a Superior Court to find this unconstitutional," Jones said. "A Superior Court would tend to be restrained, unless a statute appears to be so flawed on its face they have to rule against it."
Amann disagreed: "The primary duty of the Superior Court is to follow the law as it's given."
Introducing the issue now also raises the possibility that it could be used as grounds for appeal.
"This is a death-penalty case," Jones said. "You want to raise all the potential legal issues that you can."
But that point could be blunted if prosecutors do not opt to use the wiretaps in their case.
"I've listened to hours of wiretaps that include nothing but the participants talking about what they were watching on 'Oprah' at the same time," Amann said. "Telephone conversations can be quite meaningless. We can, on the other hand, envision a conversation that could be the equivalent of a confession. It's impossible to speculate."
Bee staff writer John Coté can be reached at 578-2394 or email@example.com.