Judge Gregory Caskey said that Richmond police Sgt. Lori Curran appears to have violated Cody Smith's Miranda rights during a police interview the Monday after the alleged attack.
Caskey also said that after watching the tape of Smith's three-hour interview, it is his opinion that it was more of an interrogation than a witness interview.
Curran testified earlier today that she picked Smith up at school Oct. 26 and brought him to the police station, where she interviewed him.
Curran testified that at one point in the interview when Smith asked if he could go home she told him no.
When he tried to invoke his right to remain silent, Curran continued to interview him, Caskey said.
"He invoked his right to remain silent and she deliberately chose to proceed," Caskey said.
The statements Smith did make during the interview were vague and inconsistent, Caskey added.
Smith's attorney David Headley said he believed the judge made the right decision by excluding the interview and that it is his belief that Smith did not engage in any sexual or violent behavior that night.
Curran was the 20th and final witness called by the prosecution in the preliminary hearing in the case, which began Nov. 15.
Attorneys are expected to present their oral arguments Tuesday morning, after which it will be up to Caskey to decide whether there is enough evidence to bring them to trial.
The other defendants in the case include San Pablo resident Morales, 17; Pinole resident Marcelles Peter, 18; and, Richmond residents Jose Montano, 19, and Elvis Torrentes, 22, Manuel Ortega, 20, and John Crane Jr., 44.
Caskey said this afternoon that he has concerns about whether there is enough evidence to hold Smith and Torrentes to answer on the charges, but suggested that the evidence against the other five defendants would be enough to bring them to trial.
The alleged attack happened Oct. 24, 2009. The victim had attended the homecoming dance, but got bored and left early.
She allegedly told a nurse the following day that she had been about to call her father to have him come pick her up when Smith, who she knew from class, invited her over to a dark courtyard area on the north side of campus to drink alcohol with him and his friends.
The victim told the nurse that she remembered drinking brandy with the group, but then got dizzy and blacked out. She woke up the next day in the hospital.
After she blacked out, a large group of males reportedly beat her, robbed her and sexually assaulted her for more than two hours while others stood by and watched, police said.
By the time police found the victim shortly before midnight, she was in a coma and nearly dead, Jim Carpenter, a pediatric consultant for the county's sexual assault response team, testified earlier in the hearing.
According to Carpenter, the victim had suffered multiple severe head injuries that caused swelling in her brain. She also had numerous other scrapes and bruises all over her body. She was hypothermic and had a blood alcohol level of .355 percent.
Ortega was arrested as he left the area, police said. According to David Stockwell, a forensics supervisor for the Contra Costa County Sheriff's Office, Ortega's semen was found on the victim's body, and the victim's DNA was found on Ortega's body.
Several investigators have testified that witnesses allegedly described Ortega as the leader of the group and said he beat the victim and repeatedly kicked her and punched her in the head while he tried to force her to give him oral sex.
DNA from Peter and Montano was also found at the scene, along with DNA from Crane, 44, who was arrested two months after the alleged attack on a cold-hit DNA match, police said. His semen was found on numerous parts of the victim's body, Stockwell said.
Stockwell also found DNA from several people who have not been identified.
DNA from Smith, Morales and Torrentes was not found at the scene or on the victim, Stockwell said.
Richmond police Detective Stina Johanson, however, said she found the victim's cell phone in Smith's dresser drawer, and Peter allegedly admitted that he fondled the victim, Johanson said.
Morales allegedly admitted to a different investigator, Richmond police Detective Ken Greco, that he inserted the antenna of a walkie-talkie into the victim, urinated on her and stole her ring, Greco said.
Statements from several of the defendants have allegedly placed Torrentes, or someone who looked like Torrentes, at the scene, according to detectives.
The hearing is scheduled to continue, and likely conclude, Tuesday in Contra Costa County Superior Court in Martinez.