"There are some contexts in which the risk that the jury will not, or cannot, follow instructions is so great, and the consequences of failure so vital to the defendant, that the practical and human limitations of the jury system cannot be ignored. Such a context is presented here, where the powerfully incriminating hearsay statements of a codefendant are deliberately spread before the jury in a joint trial.
"We hold that, because of the substantial risk that the jury, despite instructions to the contrary, looked to the incriminating hearsay statements made by Evans in determining Bruton's guilt, admission of Evans' confession in this joint trial violated Bruton's right of cross-examination secured by the Confrontation Clause of the Sixth Amendment."
Because of the Bruton rule, officers should not assume that one suspect's full confession will be adequate proof of non-confessing suspects' guilt. To avoid Bruton error, the prosecutor in such a case must either "redact" (edit) the confession to eliminate all references to the fact that others were also involved, or "sever" the defendants for separate trials.
Bruton Technique
When you arrest two or more suspects, it's important to make every lawful effort to get confessions from each of them. Every perpetrator should admit his or her own, personal involvement in the crime. In order to make each defendant's statement admissible in a joint trial, an interrogating officer should take two statements—one in which the suspect tells everything that everyone did, and a second one in which he talks only about his own actions. Each defendant's separate personal confession can then be used against him in a joint trial, without violating any codefendant's confrontation rights.