Can a plea bargain that binds the witness only to testify truthfully and not in a prearranged fashion be deemed invalid?

that binds the witness only to testify truthfully, and not in a prearranged fashion, cannot be deemed invalid.].) These principles are violated only when the agreement requires the witness to testify to prior statements regardless of their truth, but not when the truthfulness of those statements is the mutually shared understanding of the witness and the prosecution as the basis for the plea bargain. ( People v. Boyer, supra, 38 Cal.4th at p. 456, 42 Cal.Rptr.3d 677, 133 P.3d 581.)