In People v. Mahboubian, 74 N.Y.2d 174, 186-188, 544 N.Y.S.2d 769(1989), the Court of Appeals defined the standard that must be utilized by a court when determining if a party or parties have demonstrated good cause, such as to override the strong public policy favoring joinder, "concluding that severance is compelled where the core of each defense is in irreconcilable conflict with the other and where there is a significant danger, as both defenses are portrayed to the trial court, that the conflict alone would lead the jury to infer defendant's guilt." The Court of Appeals observed that "motions for severance typically arise at the pretrial stage or in the course of trial" (so that) "the trial court must apply this standard prospectively, based on its discretionary assessments of the strategies and evidence as forecast by the parties" (People v. Mahboubian, supra).