In Alvarado v. Superior Court (2000) 23 Cal.4th 1121, the defendants were charged with the murder of a fellow inmate. (Id. at p. 1126.) When the defendants requested the prosecution witnesses' names and addresses, the prosecution sought a protective order. (Id. at p. 1128.) At a series of in camera hearings, the prosecution presented evidence of the following: the killing was ordered by the Mexican Mafia; the defendants participated in the killing to gain favor with the Mexican Mafia; the Mexican Mafia was known for retaliatory acts against government witnesses; the Mexican Mafia employed a sophisticated procedure for issuing contracts to kill witnesses; one of the witnesses was attacked in jail after the charged killing; and another witness was threatened. (Id. at pp. 1128-1129.) The trial court ordered that the witnesses' identities be permanently withheld from the defense and that the witnesses were to be produced for an interview by the defendant within 30 days of trial. (Id. at p. 1130.) On appeal, the defendants conceded that disclosure of the witnesses' identities constituted good cause under section 1054.7, but argued that withholding disclosure of their identities at trial violated their federal constitutional rights to due process and to confront witnesses against them. (Id. at p. 1134.) Alvarado held that the order was valid insofar as it protected the witnesses' identities before trial, but that the witnesses could not testify anonymously at trial. (Id. at pp. 1136, 1149.)