In Davis v. Washington, the recorded 911 call of a [possibly] battered woman was admitted into evidence. The woman herself did not testify. In Hammon v. Indiana, a first responder (a police officer) to a 911 call witnessed statements made by a battered woman, and repeated those statements at trial. The battered woman, again, did not testify. Both statements were allowed in under the hearsay exception commonly known as the excited utterance exception (Indiana does not have a residual hearsay exception, and the body of law from that state is quite muddled. Indeed, some 'excited utterances' were made up to an hour after the startling incident, clearly quite far from the standard approach under the federal rules.). To get a full understanding of the facts, read this synopsis from Duke Law School. The facts are quite important, because these cases (and future cases of a similar ilk) are incredibly fact-dependent. The synopsis is reasonably accurate, although I would add that in Davis, the woman began the 911 call while she was still under attack. Also, in Hammon, the woman initially told the officers that nothing was wrong, and later reversed herself. Also, as soon as she finished giving the statement that was later admitted, the officer asked her to sign an affidavit, which was also admitted at trial, and was struck down as testimonial by the appellate courts. The affidavit and the statement were identical in content.
There were a number of different standards offered for the Court. Professor Richard Friedman of Michigan, representing petitioner Hammon, sought the Court to declare that any and all accusatory statements made to known law enforcement officials (police officer, 911 operator, court official, etc., but NOT an undercover agent) are per se testimonial, regardless of whether or not they fall within one of the historically recognized hearsay exceptions. Indiana offered what it called the "resemblance test" with a immediate danger corollary. This test would exclude anything that resembled the historical abuses that Crawford appeared to state that the confrontation clause was originally designed to combat, specifically, inquisitorial abuses by the state such as Raliegh's Case. The immediate danger corollary was advanced as the principle argument by the United States, and offered that statements made to police officers during the initial stage of their investigation were for the purpose of establishing the danger to the officer and the declarant, and was admissible. Once the declarant was no longer in danger, statements were no longer made for that purpose, and would be excluded during trial. The other potential test is the reasonable declarant test, which offers that statements made by a declarant who should have a reasonable belief that they might be used for an investigatory purpose would be testimonial and inadmissible.
Numerous amici briefs were filed for the states in these cases, many from battered women's organizations. Because many victims of domestic violence are unwilling (some are unable) to testify at trial, the state is often in a difficult bind. They have no evidence other than hearsay statements because the victim is nowhere to be found. Further, the victim is often coerced or threatened by the batterer into not testifying. Professor Friedman argued that such activities, because they are illegal, would subject the defendant to forfeiture, and allow the judge to admit the hearsay. However, an evidentiary hearing would still be required to allow that hearsay, and the woman would, presumably, still not testify, meaning that the judge would be very hard pressed to find that the tampering occurred. As such, these cases present not only a very interesting constitutional issue and a complicated evidentiary issue, they also present an important social issue (In fact, Oregon and California have already altered their states' rules of evidence to allow virtually all hearsay-type evidence in domestic violence cases.).
While it is dangerous to use the oral arguments as a predictor of the outcome of the cases, I will now do so. It was clear that Justice Scalia was immediately on the side of the petitioners in both cases. In fact, in Hammon, there were few encouraging comments from ANY of the justices. Justice Ginsburg, whose questioning the entire day focused almost solely on the domestic violence issue, might be the only vote for Indiana, and even her vote is unlikely. In Hammon, it would not at all surprise me to find a unanimous decision in favor of the petitioner. In Davis, a much closer case, Washington might very well find 5 votes. I would think it unlikely for Ginsburg or Breyer to side with the petitioner, and, from their questions, Roberts, Alito, Souter seemed well-disposed to the state's argument. Kennedy, Stephens, and Thomas remained mostly silent, and gave no real indications of their positions.