Does a judge have to make a determination of a factual issue relating to the merits of the case?

In Kohn v. Superior Court, 239 Cal.App.2d 428, 48 Cal.Rptr. 832, it was held that a judge in ruling on a motion under section 995 of the Penal Code was not making a determination of a factual issue relating to the merits of the case. The rationale there set out at pages 430 and 431, 48 Cal.Rptr. at page 834 was that in such a ruling "... the court merely reviews the evidence. It does not substitute its judgment as to the weight thereof ... nor does it resolve conflicting factual contentions.... The function ... involves the determination which relates to contested fact issues. He must have actually resolved or determined conflicting factual contentions relating to the merits prior to trial before the right to disqualify is lost."