What is the state's duty to preserve and preserve evidence in the context of a sexual assault case?

destroyed, the Trombetta approach applies and the state has a duty to preserve it. But "[t]he state's responsibility is [more] limited when" the evidence was merely potentially useful. In that case, the state breaches its duty only if it acts in bad faith. (People v. Beeler, supra, 9 Cal.4th at p. 976.)

If a defendant demonstrates that significant exculpatory evidence was lost or establishes bad faith in connection with the loss of potentially useful evidence, then the trial court has discretion to impose appropriate sanctions. (People v. Medina (1990) 51 Cal.3d 870, 894.)

Negligent destruction or failure to preserve potentially exculpatory evidence, without evidence of bad faith, will not give rise to a due process violation. (Youngblood, supra, 488 U.S. at p. 58.) A finding as to "whether evidence was destroyed in good faith or bad faith is essentially factual: therefore, the proper standard of review is substantial evidence." (People v. Memro (1995) 11 Cal.4th 786, 831.) On review, this court must determine whether, viewing the evidence in the light most favorable to the trial court's finding, there was substantial evidence to support its ruling. (People v. Carter (2005) 36 Cal.4th 1215, 1246.)