What is the test for severance of a murder case?

"`"The burden is on the party seeking severance to clearly establish that there is a substantial danger of prejudice requiring that the charges be separately tried." [Citation.] ... [] ... Refusal to sever may be an abuse of discretion where: (1) evidence on the crimes to be jointly tried would not be cross-admissible in separate trials; (2) certain of the charges are unusually likely to inflame the jury against the defendant; (3) a "weak" case has been joined with a "strong" case, or with another "weak" case, so that the "spillover" effect of aggregate evidence on several charges might well alter the outcome of some or all of the charges; and (4) any one of the charges carries the death penalty or joinder of them turns the matter into a capital case.'" (People v. Bradford (1997) 15 Cal.4th 1229, 1315, 65 Cal.Rptr.2d 145, 939 P.2d 259.)

With respect to the first factor, defendant contends that if the three murder counts had been tried separately, evidence of the other two would not have been cross-admissible in any other trial because the crimes bore no common identifying characteristics and thus were not probative of any of the factors listed in Evidence Code section 1101, subdivision (b). But, as we explain, even if we assume that the standards for cross-admissibility in the prosecution's case-in-chief were not satisfied here (see People v. Mason, supra, 52 Cal.3d at p. 934, 277 Cal.Rptr. 166, 802 P.2d 950), the evidence of the other two murders would have been cross-admissible on rebuttal in each other case if tried separately.