What is the test for a motion for mistrial?

In reviewing rulings on motions for mistrial, we apply the deferential abuse of discretion standard. ( People v. McLain (1988) 46 Cal.3d 97, 113, 249 Cal.Rptr. 630, 757 P.2d 569.) A mistrial should be granted if the court is apprised of prejudice that it judges incurable by admonition or instruction. [Citation.] Whether a particular incident is incurably prejudicial is by its nature a speculative matter, and the trial court is vested with considerable discretion in ruling on mistrial motions. [Citation.] ( People v. Haskett (1982) 30 Cal.3d 841, 854, 180 Cal.Rptr. 640, 640 P.2d 776.)