Concurring.—In deciding on a rule of practice, it is appropriate to keep in mind the purpose to be served by the proposed rule and the history of the legal problem involved. Here, the discovery sought is not for purposes of substantive defense but solely to discover whether there might be a possibility of traversing the affidavit supporting the search warrant.
Thus, the need for the discovery sought here is far less compelling than discovery directly relating to guilt or innocence. (See City of Santa Cruz v. Municipal Court (1989) 49 Cal.3d 74 [260 Cal.Rptr. 520, 776 P.2d 222].) Even if the requested discovery were to reveal some basis for believing the statement concerning the informant’s reliability was false or incorrect, the defendant would still have to demonstrate the inaccuracy or falsity was material to the issuance of the warrant by the magistrate.
In light of the foregoing, I agree with the analysis and formulations in the majority opinion. What makes the application of the majority’s formulations somewhat dissatisfying in this case is that defendant would be required to cast reasonable doubt on the veracity of a statement which contains virtually no facts to controvert, only the conclusion of the affiant. The only statement in the affidavit relating to the informant reads in its entirety: “Within the past ten days, I met with an informant who has, in the recent past, given me information about drug dealers which later proved to be reliable.”
I agree with the dissenting opinion that it would be almost impossible for anyone to cast reasonable doubt on the veracity of this conclusional statement. But the remedy for this problem is not to require less from the defendant seeking discovery but, rather, to require more factual data to be included in the affidavit to support the showing of the informant’s reliability, so that the magistrate is not required to rely on the affiant’s conclusions *26or opinion as to the informant’s reliability and so a challenging defendant would have some facts to controvert.
In the case at bench, however, the sufficiency of the affidavit on its face to establish the reliability of the informant was apparently never challenged by an appropriate motion. Had it been, I would hold it insufficient and disapprove any decisions to the contrary.