There's a hearsay exception for what the courts call "state of mind". It involves extrajudicial declarations "made by a person who cannot be called as a witness, and relied upon solely to show an existing intention or state of mind of the declarant, are admissible in evidence as an exception to the hearsay rule provided such declarations appear to have been made in a natural manner, not under circumstances of suspicion, and that they are material and relevant to the issue involved." This comes from a famous case in 2000 of Commonwealth v. Begley.
Similarly, a deceased victims out-of-court statements evincing an intent to meet the defendant shortly before the killing were admissible under the exception as circumstantial proof that the victim acted in accordance with his or her stated intent, thereby providing the defendant with an opportunity to commit the crime in question. A murder victim's statement that he intended to confront the defendant was admissible as a state of mind exception. This was a case of Commonwealth v. Stallworth from 2001 where the victim sought a PFA order and allegations therein were relevant to establish the motive of the defendant.
Finally, in Commonwealth v. Laich from 2001, it was ruled that the trial court erred in admitting statements made by a victim to the effect that the defendant had said that if he ever caught her with another man he would kill them both. The victims state of mind concerning her relationship with the defendant was completely irrelevant to the defendants degree of guilt.
Finally, in Commonwealth v. Laich from 2001, it was ruled that the trial court erred in admitting statements made by a victim to the effect that the defendant had said that if he ever caught her with another man he would kill them both. The victims state of mind concerning her relationship with the defendant was completely irrelevant to the defendants degree of guilt.