What is the prosecutor's duty not to suppress or otherwise make unavailable evidence in post-conviction proceedings?

A prosecutor's responsibilities in the pretrial context are clear. (See, e.g., In re Ferguson, supra, 5 Cal.3d 525, 96 Cal.Rptr. 594, 487 P.2d 1234; People v. Ruthford (1975) 14 Cal.3d 399, 121 Cal.Rptr. 261, 534 P.2d 1341.) This same duty not to suppress or otherwise make unavailable evidence favorable to the defendant (id., at p. 406, 121 Cal.Rptr. 261, 534 P.2d 1341) must also apply to postconviction proceedings. To rule otherwise would be to limit the availability of remedies created to vacate erroneous convictions.