O'ROURKE, J.

Petitioners Tom Hornung, warden at R.J. Donovan Correctional Facility, and James W. Nielsen, Chairman of the Board of Prison Terms, seek a writ of mandate to compel respondent superior court to grant their motion to quash subpoenas for two commissioners of the Board of Prison Terms to appear at evidentiary hearings pursuant to orders to show cause granted as to the writs of habeas corpus of Ronald Zych and William Henry Jackson (Real Parties). Petitioners contend the court should have granted the motion to quash because the separation of powers doctrine and the deliberative process privilege protect the commissioners from testifying as to their decisions; judicial inquiry into the commissioners' job qualifications is inappropriate; and the commissioners may not be questioned as to bias. Because we agree the separation of powers doctrine prevents Real Parties from questioning the commissioners, we grant the petition for writ of mandate.

FACTUAL AND PROCEDURAL BACKGROUND

The court issued an order to show cause in each case and scheduled evidentiary hearings. On November 22, 1999, Real Parties subpoenaed Deputy Commissioner Carol Bentley and Commissioner Thomas Giaquinto to appear at the evidentiary hearings. On November 30, Petitioners filed motions to quash the subpoenas. After a hearing, the court issued an order denying the motions to quash but limiting the commissioners' testimony to training, policies, and evidence about the Respondents' specific cases.

DISCUSSION

We first deal with Real Parties' contention that writ review is not available. We agree writ review is not generally available to resolve the admissibility of evidence, which is normally resolved by appeal. ( People v. Municipal Court (Ahnemann) (1974) 12 Cal.3d 658, 660.) "However, `when the remedy by appeal is rendered inadequate in the context of a specific case, this court may, in its discretion, permit an aggrieved party to bypass the appellate process and pursue extraordinary relief.' [Citation.]" ( Silva v. Superior Court (1993) 14 Cal.App.4th 562, 573-574.) A court may issue a writ of mandate when "`the issues presented are of great public importance and must be resolved promptly.' [Citation.]" ( Anderson v. Superior Court (1989) 213 Cal.App.3d 1321, 1328.) For example, writ review of pretrial evidentiary rulings was available in a case of multiparty, complex litigation. ( Vermeulen v. Superior Court (1988) 204 Cal.App.3d 1192, 1196.) Here, we address an issue concerning the separation of powers, a matter of great public importance, where courts have routinely issued writs to prevent pretrial discovery. ( County of Los Angeles v. Superior Court (1975) 13 Cal.3d 721 [writ issued to override the court's order allowing deposition of legislators concerning a specific topic as it related to the passage of legislation]; State Board of Pharmacy v. Superior Court (1978) 78 Cal.App.3d 641 [writ issued to quash subpoena to depose Attorney General].) In addition, writ review is necessary to protect the nine Board of Prison Term commissioners from the burden of attending evidentiary hearings throughout the state. (Compare People v. Arbuckle (1978) 22 Cal.3d 749, 754 [burden on correctional officers if required to testify regarding probation reports].)

An administrative officer performing a quasi-judicial function may not be questioned about his mental processes. ( State of California v. Superior Court (1974) 12 Cal.3d 237, 257-258.) In United States v. Morgan (1941) 313 U.S. 409, the Court held the Secretary of Agriculture should not have been called as a witness and questioned "regarding the process by which he reached the conclusions of his order, including the manner and extent of his study of the record and his consultation with subordinates." ( Id. at p. 422.) "Just as a judge cannot be subjected to such scrutiny [citation], so the integrity of the administrative process must be equally respected. [Citation.]" ( Ibid.) The commissioners perform a quasi-judicial function when they decide to grant or deny parole. ( Sellars v. Procunier (9th Cir. 1981) 641 F.2d 1295, 1304.) Therefore, the constitutional doctrine of separation of powers precludes the court from inquiring into the mental processes or motivation that underlie the commissioners' actions. ( In re Johnson (1995) 35 Cal.App.4th 160, 170, fn. 8; In re Fain (1976) 65 Cal.App.3d 376, 393, fn. 14.)

Here, the court recognized the commissioners could not be questioned about mental processes and limited Real Parties' questions, as follows:

"Petitioners clearly may not question the commissioners about their political motivations or their mental processes, nor may they question the commissioners about the specifics of any other cases not relevant to the instant proceedings. The commissioners may, however, be questioned as to their training procedures, their written and oral directives or policies that control or attempt to control suitability and release date hearings for life prisoners and the materials or information provided about the Petitioners' specific cases."

Unfortunately, the court's attempt to limit the commissioners' testimony still violates the separation of powers doctrine. First, the law clearly holds that a court may not inquire as to what materials a quasi-judicial officer reviewed and relied upon in making a decision. ( State of California v. Superior Court, supra, 12 Cal.3d at p. 258.) Such inquiry was precisely what the Supreme Court derided in United States v. Morgan. Second, the distinction the court attempted to draw between the training and the written and oral directives that are controlling in a parole suitability and release date hearing — on the one hand — and the mental processes that result in a decision — on the other hand — is a distinction without a difference. The training and the written and oral directives are merely components of the mental processes a decision maker applies when coming to a judgment.

Real Parties argue they should be able to question the commissioners as to their after-the-fact bias as part of the due process issues Real Parties raised. Real Parties correctly contend they are entitled to due process ( In re Minnis (1972) 7 Cal.3d 639, 649), which includes having an impartial hearing, "free from bias or prejudice." ( O'Bremski v. Maass (9th Cir. 1990) 915 F.2d 418, 422.) The California Code of Regulations, title 15, section 15:2250 defines an impartial panel as one whose members do not have a specific prejudice for or against the particular prisoner. Real Parties have made no showing of such individualized prejudice.

Real parties incorrectly presume bias means a generalized prejudice against all criminals. Such views are, however, not evidence of bias:

"The right to an impartial trier of fact is not synonymous with the claimed right to a trier completely indifferent to the general subject matter of the claim before him. . . . [T]he word bias refers `"to the mental attitude or disposition of the judge towards a party to the litigation, and not to any views that he may entertain regarding the subject matter involved.'" In an administrative context, Professor Davis has written that `Bias in the sense of crystallized point of view about issues of law or policy is almost universally deemed no ground for disqualification.' [Citations.] This long established, practical rule is merely a recognition of the fact that anyone acting in a judicial role will have attitudes and preconceptions toward some of the legal and social issues that may come before him." ( Andrews v. Agricultural Labor Relations Bd. (1981) 28 Cal.3d 781, 790-791.)

In fact, Real Parties' argument is that the commissioners have not followed the law and the policies that have been adopted as regulations. As with any other supposed breakdown in the administrative or judicial process, Real Parties' remedy is to have a court review the record and other admissible evidence in accordance with applicable legal standards. As part of that process, the separation of powers doctrine bars a court from placing the decision makers on the stand to inquire into their mental processes.

DISPOSITION

We Concur:

BENKE, Acting P.J.

McINTYRE, J.

The petition of petition of petitioner Tom Hornung for review by the Supreme Court was denied September 27, 2000. Brown, J., did not participate.