In State v. Kendrick, 538 P.2d 313 (Utah 1975) the defendant was convicted of robbery. His "co-perpetrator was tried first and later gave testimony inculpating the defendant. at Kendrick's trial, the co-perpetrator refused to testify . . . ." State v. Villarreal, 889 P.2d at 424. Instead, his "prior testimony inculpating Kendrick was then read to the jury." Id. Similarly, in Villarreal, the defendant's co-perpetrator in a kidnaping and rape case was tried first and then refused to testify at the defendant's trial. While the co-perpetrator was on the stand at Villarreal's trial, the prosecutor recited to him a laundry list of factual propositions in the form of leading questions based on his earlier confession of Villareal's involvement in the crime; the co-perpetrator did not respond. See id. at 422-23. Both Kendrick and Villarreal turned on the principle that a defendant must be given an effective opportunity to cross-examine the witnesses called against him. See Villarreal, 889 P.2d at 425 (requiring an "effective opportunity to cross-examine" the witness "on facts that were central to establishing the defendant's guilt"); Kendrick, 538 P.2d at 315 (stating that the "right of confrontation is based upon the notion that the accused should have an opportunity to cross-examine the witnesses against him").