What is the test for a defendant to oppose a motion to amend their criminal record to include a prior conviction?

The available case law does not compel a contrary result. In People v. Payton (1939) 36 Cal.App.2d 41, 96 P.2d 991, decided before the amendment of section 969a and while that section remained phrased as mandatory, the trial court permitted without discussion an amendment which added a prior conviction. The defendant did not object at trial but attacked the amendment on appeal. The reviewing court stated, "the [trial] court had the right to permit the filing of the amended information; indeed it was plainly the duty of the court so to do (Pen.Code., 969a); and such action of the court would not have been subject to objection, if any had been made." (Id., at p. 59, 96 P.2d 991.)

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