This was a case about hearsay evidence and when such evidence can be used in a court of law.
In this case, the police were called to the Hammon home because of a domestic disturbance. They saw broken glass in the living room. They questioned the couple separately. Mrs. Hammon said that she had been assaulted by her husband and signed a statement to that effect. At trial, Mr. Hammon argued his wife’s statement could not be admitted because it was hearsay.
In this case, hearsay is admissible if it is not “testimonial.” That is, if the statement was made in order to preserve the statement as evidence, it is “testimonial” and cannot be admitted. By contrast, if the statement was made simply to help the police with their investigation (to help them determine what to do right then at the Hammon home) it is a non-testimonial statement and it can be admitted into evidence.
In this case, the Supreme Court held that Mrs. Hammon’s statement was testimonial. When it was made, there was no longer an emergency and no threat to her. Therefore, there was no need for a non-testimonial statement to help the police figure out what was going on.
This case, then, was about what sorts of hearsay statements are admissible in court.