The opinion of the court was delivered by: Franson, J.
CERTIFIED FOR PUBLICATION
ORIGINAL PROCEEDING; petition for writ of habeas corpus.
Petitioner John Fratus was found guilty following a disciplinary hearing for battery of a correctional officer in 2006. He filed a petition for writ of habeas corpus in this court in 2008, alleging he did not have a fair hearing because he had not been allowed to call a friendly witness and had not been permitted to cross-examine the prison officers who testified against him at the disciplinary hearing. This court issued an order directing the Department of Corrections and Rehabilitation (the Department) to "show cause before the Kings County Superior Court ... why petitioner is not entitled to appropriate relief." In February 2009, the superior court denied the petition for writ of habeas corpus. Although the superior court found that the Department had violated its own regulation, which permitted an inmate at a disciplinary hearing to "ask questions of all witnesses called" (Cal. Code Regs., tit. 15, § 3315, subd. (e)(5)), it found the error harmless.
Fratus then filed the current petition for writ of habeas corpus in this court in August 2009. Again, he contends he was denied his right to call a friendly witness and to cross-examine witnesses at his disciplinary hearing. In addition, based on his inability to fully present his case, he contends there was insufficient evidence to support the guilty finding. This court again issued an order to show cause, but returnable to this court. As we shall explain, because the Department has conceded that Fratus was permitted to ask only one question of each of the four officer witnesses who gave evidence against him, we agree with the superior court that the Department violated its own regulation allowing an inmate to ask relevant questions of all witnesses called. But unlike the superior court, we do not view the error as harmless. We also conclude the Department, in this case, violated Fratus's due process right to call witnesses in his defense and the Department's own regulation to question all witnesses. Accordingly, we grant the petition for a writ of habeas corpus and direct the Department to either restore to Fratus the 121 days of good-time behavior credits he lost as a consequence of the Department's finding that he had committed a battery upon a correctional officer or conduct a new disciplinary hearing consistent with this opinion.
BACKGROUND FACTS AND ADMINISTRATIVE PROCEEDINGS
At the time of the alleged incident and disciplinary hearing, Fratus was serving time for a 2005 conviction of shooting into an inhabited dwelling (Pen. Code, § 246)*fn1 and assault with a firearm (§ 245, subd. (a)(2)). He was later convicted in 2008 of "gassing" a peace officer (§ 4501.1, subd. (a)); and in 2009 of obstructing/resisting an officer (§ 69). For these offenses, he is serving a total prison term of 44 years and therefore is in the lawful custody of the Department.
On July 18, 2006, prison officials issued Fratus a disciplinary rules violation report for battery on a peace officer, which allegedly occurred on July 12, 2006. The Department's account of the incident differs drastically from petitioner's account.
According to the Department, Correctional Officers Hamilton and Solano were escorting Fratus from his cell to an outdoor exercise module. Fratus was very agitated, used profanities, and was resistant toward the escorting officers, so Sergeant Robertson counseled Fratus about his improper behavior. Fratus then head-butted Hamilton on the left side of Hamilton's face. Hamilton and Solano forced Fratus to the ground to subdue him. Officer Cortez relieved Officer Hamilton and assisted Officer Solano in escorting Fratus back to his cell. Fratus attempted to spit on, trip, and lunge at Officer Cortez, requiring the officers to force Fratus to the ground two more times in order to subdue him.
Fratus asserts that the Department's account of the incident is false, and that the Department fabricated the event to conceal an unprovoked beating of him by correctional officers. He contends that the alleged beating was inflicted because he had recently been transferred to Corcoran from another prison, and the Corcoran correctional officers were aware that he had "write-ups for masturbating in [his] cell and indecent exposure in front of female prison staff/officers" at the other prison. Fratus contends that shortly before the alleged beating Officer Solano told him "welcome to Corcoran, you're gonna see what we do at Corcoran, you like to jack off in front of women?"
Before his disciplinary hearing in August 2006, Fratus received the services of an investigative employee (the investigator), whose duties were to act as a fact finder for the Senior Hearing Officer (SHO) who would preside over the disciplinary hearing. In compliance with Fratus's requests, the investigator interviewed or attempted to obtain statements from four correctional officers involved in the incident and 17 inmates who were housed in cells in that area on July 12. Fifteen of the 17 inmates refused to give a statement. One said "I don't know anything." The remaining inmate, Herman Johnson, gave a statement supportive of Fratus. The investigator's report describes Johnson's statement as follows: "I saw Inmate Fratus being escorted to the yard. The next thing I know he was being slammed to the ground and the Correctional Officer lied on Fratus and said he tried to assault them. That was their reason for slamming him to the ground. I saw the entire thing. Fratus did not make any moves or anything of that nature. The C/O's are lying so they can justify why they beat him up. Then as they were walking him out of the cages they threw him down to the ground again and kicked him in the face multiple times. And again they kicked him some more." Fratus timely received a copy of the investigative employee's report before his August 23, 2006, disciplinary hearing.
The investigator's report also included statements taken from four officers involved in the July 12 incident: Officer E. Hamilton (the alleged victim of the July 12 head-butting), Sergeant D. Robertson, Officer R. Cortez, and Officer R. Solano. Those statements appear to be in accord with the Department's account of the incident as described above. Hamilton's statement also adds that after Fratus head-butted him and after Fratus attempted to trip Cortez and was taken to the ground a second time, an Officer R. Ortega placed leg irons on Fratus. Hamilton's statement also adds that after Fratus lunged at Cortez and was taken to the ground for the third and final time, an Officer K. Elze relieved Officer Solano, and Elze and Solano placed Fratus into a holding cell.
The SHO denied Fratus's request for the presence of inmate Johnson at the disciplinary hearing, concluding that Johnson's live testimony would not provide any additional or relevant information beyond what was contained in his earlier statement to the investigator, quoted above. The SHO granted Fratus's request to have five custodial officers testify, but Fratus later waived his right to call Officer Solano at the hearing, after Solano was apparently unavailable to appear. He entered a plea of not guilty and stated: "I did not assault anyone. I was the one who was assaulted." Officer Hamilton, Sergeant Robertson, Officer Cortez and Officer Elze were questioned at the hearing.
The SHO's report describes the live testimony given at the hearing by these officers, in response to questions posed by the SHO:
"The following questions were asked of Officer Hamilton:
"Q1) Were you one of the escorting officers?
"Q2) Did this incident occur outside, or inside the exercise module?
"Q3) Did you witness Inmate Fratus head butt Correctional Officer Hamilton?
"A3) Yes, right at the door of the exercise module.
"The following questions were asked of Correctional Sergeant Robertson:
"QA) Were you one of the escorting ...