VALLEJO, Calif. (KGO) -- New details have emerged on the Vallejo kidnapping, dubbed the real life "Gone Girl" case.
The FBI obtained an arrest warrant back in June for Matthew Muller for the kidnapping of Denise Huskins.
Huskins disappeared in March from her Vallejo home and turned up in Southern California. Vallejo police originally said she faked the entire disappearance.
Muller's attorney now says a key piece of evidence linking his client to Huskins disappearance and another crime in Dublin should be thrown out.
Muller appeared in court Thursday wearing a red jumpsuit. At times he smiled at his attorney. Thursday's hearing was continued to next week. That's when Muller's attorney Thomas Johnson will argue that detectives lack of a search warrant for a cellphone is reason enough to unravel this case.
In the early morning hours of June 5, Dublin Police Services responded to a home invasion robbery. The victims fought off the suspect who fled, but he left behind a key piece of evidence.
"He left his cellphone at the residence," said Dublin police Lt. Herb Walters.
The cell phone was locked, so detectives made an emergency 911 call. An operator gave them the phone's number, which they then used to obtain the registered owner of the phone.
That information brought detectives to Matthew Muller's parents and then to him at a South Lake Tahoe home. There, investigators found even more evidence allegedly linking him to the March Vallejo home invasion and kidnapping of Denise Huskins.
Prior to that evidence, Vallejo police had been calling the kidnapping a hoax. In late June, FBI agents obtained a warrant for Muller in connection with the Vallejo kidnapping while he was already in jail facing charges in the Dublin home invasion.
"They just put the case together and it turned out great," Walters said.
Muller's attorney Thomas Johnson now claims detectives searched the phone without a warrant.
"The phone is really a window into the entire investigation," Johnson said.
If the search of the phone is suppressed, Muller's Attorney said, "I don't know what evidence would remain."
Vallejo home invasion victim Denise Huskins is not a party in the Alameda County Case but her attorney told ABC7 news he recognizes the implications the motion could have in a subsequent federal case.
"I'm glad the right person was apprehended. It would be tragic if this case is dismissed on a technicality. While clever, this argument ultimately has no merit," said Douglas Rappaport during a phone interview.
A judge will make that decision when the motion is heard next week.
Click here for full coverage on the Vallejo "Gone Girl" kidnapping.