MEMORANDUM *
Fred Graves, a California state prisoner, appeals the district court’s denial of his 28 U.S.C. § 2254 habeas petition, in which he claimed his due process rights were violated when he was found guilty of distribution of a controlled substance in prison disciplinary proceedings. As the parties are familiar with the facts of this case, we do not separately recount them here. We have jurisdiction pursuant to 28 U.S.C. §§ 1291 and 2253, and we affirm.
I.
In Wolff v. McDonnell, 418 U.S. 539, 94 S.Ct. 2963, 41 L.Ed.2d 935 (1974), the Supreme Court explained that “[pjrison disciplinary proceedings are not part of a criminal prosecution, and the full panoply of rights due a defendant in such proceedings does not apply.” Id. at 556, 94 S.Ct. 2963. The Court stressed that “[pjrison officials must have the necessary discretion to keep the hearing within reasonable limits and to *672refuse to call witnesses that may create a risk of reprisal or undermine authority, as well as to limit access to other inmates to collect statements or to compile other documentary evidence.” Id. at 566, 94 S.Ct. 2963. While an inmate has the right to present evidence in his defense, the Court found that an inmate does not have the right to confidential, irrelevant, or unnecessary information. Id.
A.
Graves contends that his right to due process was violated by the senior hearing officer’s (SHO) denial of his request to call Officers McCoy, Meadows, and Shambre, and his cellmate Collins as witnesses. This argument fails. The SHO did not violate Graves’ due process rights process because Graves’ proposed witnesses could not provide any relevant information. Neither McCoy, Meadows, nor Shambre was present during the cell search and none had any information pertaining to Graves’ knowledge of the heroin stashed in his fan. Collins’ testimony would also have been irrelevant because Graves admitted that the fan was his, and he did not explain what additional evidence Collins could have offered or how Collins’ testimony could have supported his defense theory. Moreover, in light of all of the other evidence against him, any error that may have resulted from Graves’ inability to call Collins as a witness was harmless. See Brecht v. Abrahamson, 507 U.S. 619, 637, 113 S.Ct. 1710, 123 L.Ed.2d 353 (1993) (error deemed harmless on habeas review unless it had a “substantial and injurious” effect on the verdict).
B.
The SHO’s failure to articulate his reasons for refusing Graves’ request to ask Lt. Valencia additional questions was also harmless error. Id. The questions Graves wanted to ask Lt. Valencia would not have provided any evidentiary support for his defense theory that the heroin did not belong to him. The additional questions were irrelevant and Graves’ inability to ask these questions was therefore harmless. Id.
C.
Graves’ due process rights were not violated by the SHO’s denial of his request for records of cells searched before and after his cell search and the transcript of Officer Weston’s testimony at Collins’ disciplinary hearing. The SHO properly found that these documents were irrelevant and unnecessary to Graves’ defense. Wolff, 418 U.S. at 566, 94 S.Ct. 2963. Graves contends that he also asked to inspect the packaging material that encased the heroin. This request does not appear anywhere in the record, and even assuming that the request was made and denied, that denial did not violate Graves’ due process rights because the heroin’s packaging material was not exculpatory. If the heroin’s packaging material was old, it would not necessarily mean that Graves was not aware of the heroin in the fan. Thus, Graves’ inability to inspect the heroin’s packaging material was likely irrelevant, and certainly harmless.
D.
Due process requires a non-biased decision maker at a prison disciplinary hearing. Wolff, 418 U.S. at 570-71, 94 S.Ct. 2963. Without more, however, the mere fact that the SHO also presided over Collins’ disciplinary hearing and found Collins not guilty is insufficient evidence that he was biased against Graves. See Bostic v. Carlson, 884 F.2d 1267, 1271 (9th Cir. 1989) (finding petitioner “failed to plead any specific facts supporting his allegations that the hearing officer was biased”).
*673E.
Graves’ due process rights were not violated by his investigative employee’s failure to interview Officers McCoy, Meadows, and Shambre and his cellmate Collins before his disciplinary hearing. The investigative report prepared by his investigative employee, Officer Feryance, states that Graves only requested that he interview Officer Meadows before the hearing. And further, even if Graves did ask Feryance to interview Officers McCoy, Meadows, and Shambre and cellmate Collins, his failure to do so was harmless. See Brecht, 507 U.S. at 637, 113 S.Ct. 1710. Graves did not indicate what information they would have provided in support of his defense, and we are aware of none. Moreover, neither the officers nor Collins could offer relevant information about the search because they were not present while it took place.
AFFIRMED.
This disposition is not appropriate for publication and is not precedent except as provided by 9th Cir. R. 36-3.