This section of the sixth amendment of the U.S. Constitution is also known as the Confrontation Clause. The idea behind this amendment is that a defendant should have the opportunity to cross-examine and challenge the credibility of people making statements about him. In general, this right only applies when hearsay evidence is offered against a criminal defendant.
The Confrontation Clause is often confusing because there are many exclusions when it does not apply. In fact, the issue of exclusion was recently brought before the United States Supreme Court. In their Michigan v. Bryant decision, the Supreme Court held that the admission of a dying man's statements was not a violation of the Confrontation Clause. SupremeCourt Michigan v. Bryant.
The majority decision stated that the Confrontation Clause was not violated because the statements were not testimonial. However, in his dissent, Justice Antonin Scalia argued that this decision created another expansive exception to the clause.ABA journal 02/28/11.