Supreme Judicial Court (December 10, 2008)

The matter of how much weight is to be given a witness, particularly an expert witness, is a matter for the trier of fact, not an appellate court. This is particularly true of experts in the medical field, who regularly are permitted to testify on the basis of examination of records and other materials with respect to an issue in dispute.

The defendant was convicted of rape of a child with force. The Commonwealth filed an SDP petition pursuant to c. 123A, § 12 and the defendant was found SDP. He was committed to the treatment center for an indeterminate period. The defendant appealed and the SJC transferred the case on its own initiative.

The defendant argued that the Commonwealth's evidence was insufficient since three of the five psychologists who testified expressed opinions that the defendant was not sexually dangerous. He also argued that since one of the Commonwealth's experts never interviewed the defendant, the Commonwealth's evidence was of limited value. Therefore, he argued, the testimony and evidence in his favor was "compelling [and] scientifically objective" and asserted that no rational trier of fact could conclude otherwise. The SJC disagreed.

The law is well settled that the weight to be given to trial witnesses is a matter for the trier of fact, not an appellate court. This is particularly true of medical experts who regularly are permitted to testify on the basis of examination of records and other materials with respect to an issue in dispute. The Court also found the defendant's characterization of his witnesses' testimony as "overwhelming" to be in direct contradiction with the judge's written findings at trial. Viewing the evidence in the light most favorable to the Commonwealth, the SJC concluded that there was more than sufficient evidence for the judge to find that the Commonwealth had met its burden of proving that the defendant was an SDP.

Note: Although the defendant conceded this point, the SJC noted that it is proper for a qualified probable cause expert to testify at the commitment hearing since the statute not only specifies the particular evidence that may be introduced at a commitment hearing, but also includes the following language, "any other evidence tending to show that such person is or is not a sexually dangerous person shall be admissible at the trial if such written information has been provided to opposing counsel reasonably in advance of trial."