Is a prosecutor required to monitor every material witness in a criminal case?

"Ordinarily, '[t]he prosecution is not required "to keep 'periodic tabs' on every material witness in a criminal case"'" (People v. Herrera (2010) 49 Cal.4th 613, 630)

Page 13

because "'the administrative burdens of doing so would be prohibitive'" (People v. Fuiava, supra, 53 Cal.4th at p. 676). When, however, the prosecution has "knowledge of 'a "substantial risk"' that an '"important witness would flee,"' the prosecutor is required to '"take adequate preventative measures" to stop the witness from disappearing.' [Citation.]" (People v. Friend, supra, 47 Cal.4th at p. 68.)