What is the burden of disclosing the identity of a confidential informant?

To compel disclosure of the identity of a confidential informant, defendant has the burden to show that, "`"in view of the evidence, the informer would be a material witness on the issue of guilt and nondisclosure of his identity would deprive the defendant of a fair trial." [Citations.] That burden is discharged . . . when defendant demonstrates a reasonable possibility that the anonymous informant whose identity is sought could give evidence on the issue of guilt which might result in defendant's exoneration.' [Citation.]" (People v. Borunda (1974) 11 Cal.3d 523, 527, italics omitted; see also People v. Austin (1994) 23 Cal.App.4th 1596, 1610, disapproved on another ground in People v. Palmer (2001) 24 Cal.4th 856, 864-865.) "The existence of a `reasonable possibility' an informant could provide exonerating evidence must be determined on a case-by-case basis. [Citation.] Whether the informant could provide such evidence is always somewhat speculative. [Citation.] Where the informant is neither a participant nor an eyewitness to the charged offense the possibility is even more speculative, although still viable. [Citations.]" (People v. Austin, supra, 23 Cal.App.4th at p. 1610.)

"It is incumbent on the defendant to make a prima facie showing for disclosure before an in camera hearing is appropriate. [Citation.]" (People v. Oppel (1990) 222 Cal.App.3d 1146, 1152.) Mere speculation about evidence an informant might have is insufficient to meet defendant's burden. (People v. Luera (2001) 86 Cal.App.4th 513, 526.)