questioning him, each had to be objectively determined. If the "primary purpose" was for dealing with an "ongoing emergency", then any such statement was not testimonial and so the Confrontation Clause would not require the person making that statement to testify in order for that statement to be admitted into evidence. Exceptions to the right of confrontation In Crawford, the Supreme Court noted that two exceptions to the common law right of confrontation were acknowledged at the time the constitution was written: forfeiture by wrongdoing and dying declarations. Only the former has been explicitly adopted by the Court. Forfeiture by wrongdoing Where the defendant makes the witness unavailable for the purpose of preventing the witness from testifying, the defendant forfeits the right to confront the witness. This exception only applies to circumstances where the defendant acts with the purpose of preventing the testimony, but not to other circumstances where the defendant may nonetheless be blameworthy. For example, the testimonial statements of an uncross-examined murder victim are not admissible against the person who committed the murder unless the murder was committed for the purpose of preventing the victim from testifying. It is the prosecution's burden to prove, by a preponderance of evidence, that the defendant secured the witness's unavailability for the purpose of preventing the witness to testify. Because it is quite difficult to prove a defendant's blame, the intimidation or murder of witnesses has been a large problem in United States trials, necessitating the creation in the federal courts of a special program to relocate witnesses to prevent them from harm. </ref> "Federal Witness Protection Program: Its Evolution and Continuing Growing Pains (NCJRS abstract)". Retrieved August 12, 2020.</ref> Dying declarations Dying declarations, although noted by the Crawford Court as a historic exception to the common law right of confrontation, have not yet been explicitly acknowledged by the Court as an exception to the Confrontation Clause right. Lower courts have recognized the exception, but during oral argument in Michigan v. Bryant, the Court discussed the exception at length and frequently implied that the exception might apply, as it had done in Crawford and Giles. Harmless error and standards of review Confrontation Clause violations are usually subject to harmless error review . This means that even if evidence has been admitted in violation of the Confrontation Clause, a defendant is not entitled to a new trial if the reviewing court is convinced