U.S. v. Diaz, 59 M.J. 79

Military Justice Personnel: Court Members: Generally

1. there are limits to what a panel can be expected to disregard; the human mind of a member is not a blackboard where the judge, by a curative instruction, can irrevocably erase powerful inadmissible evidence

Core Criminal Law Subjects: Evidence: Expert / Scientific Testimony

1. M.R.E.s 702-705 and 403 operate to establish a simple four-part test for admissibility of expert testimony: (1) was the witness qualified to testify as an expert? (2) was the testimony within the limits of the expert's expertise? (3) was the expert opinion based on a sufficient factual basis to make it relevant?, and (4) does the danger of unfair prejudice created by the testimony outweigh its probative value?
2. an expert witness may not opine concerning the guilt or innocence of the accused; the limits on expert opinion are rooted in recognition that the expert lacks specialized knowledge to determine if the victim or witness is telling the truth and respect for the member’s exclusive function to weigh evidence and determine credibility
3. testimony that opines that a crime has been committed and that a particular person did it crosses the line of proper medical testimony
4. the admission of expert testimony that the accused was the perpetrator of a non-accidental trauma was plain error

Core Criminal Law Subjects: Evidence: Instructions on

1. there are limits to what a panel can be expected to disregard; the human mind of a member is not a blackboard where the judge, by a curative instruction, can irrevocably erase powerful inadmissible evidence
2. a curative instruction is the preferred remedy to purge the prejudice resulting from impermissible expert testimony

Core Criminal Law Subjects: Evidence: Other Acts

1. this Court applies a three-pronged test for determining admissibility of other-acts evidence under M.R.E. 404(b): (1) whether the evidence reasonably supports a finding by the court members that the accused committed prior crimes, wrongs or acts; (2) what fact of consequence is made more or less probable by the existence of this evidence; and (3) whether the probative value is substantially outweighed by the danger of unfair prejudice; if the evidence fails any of the three tests, it is inadmissible

Core Criminal Law Subjects: Evidence: Uncharged Misconduct

1. the prosecution cannot introduce uncharged misconduct to rebut a defense that was never raised or presented by the defense; such evidentiary bootstrapping is not permitted
2. evidence of uncharged misconduct in the form of injuries suffered by the accused’s child was inadmissible for the purpose of showing a pattern of abuse where the evidence was insufficient to establish that the accused committed the injuries; in addition, the improper expert testimony that the accused was the perpetrator of the child’s murder so fueled the prejudicial impact of the uncharged misconduct evidence that it rendered it inadmissible under the M.R.E. 403 balancing test

Core Criminal Law Subjects: Witnesses: Experts

1. M.R.E.s 702-705 and 403 operate to establish a simple four-part test for admissibility of expert testimony: (1) was the witness qualified to testify as an expert? (2) was the testimony within the limits of the expert's expertise? (3) was the expert opinion based on a sufficient factual basis to make it relevant?, and (4) does the danger of unfair prejudice created by the testimony outweigh its probative value?
2. an expert witness may not opine concerning the guilt or innocence of the accused; the limits on expert opinion are rooted in recognition that the expert lacks specialized knowledge to determine if the victim or witness is telling the truth and respect for the member’s exclusive function to weigh evidence and determine credibility
3. testimony that opines that a crime has been committed and that a particular person did it crosses the line of proper medical testimony
4. the admission of expert testimony that the accused was the perpetrator of a non-accidental trauma was plain error

Trial Stages: Merits: Mistrial

1. a mistrial is an unusual and disfavored remedy; it should be applied only as a last resort to protect the guarantee for a fair trial; declaration of a mistrial is a drastic remedy, and such relief will be granted only to prevent manifest injustice against the accused; it is appropriate only whenever circumstances arise that cast substantial doubt upon the fairness or impartiality of the trial
2. a military judge has considerable latitude in determining when to grant a mistrial; this Court will not reverse the military judge’s decision absent clear evidence of abuse of discretion
3. a curative instruction is the preferred remedy to purge the prejudice resulting from impermissible expert testimony; the granting of a mistrial is an extreme remedy which should only be done when inadmissible matters so prejudicial that a curative instruction would be inadequate are brought to the attention of the members
4. with regard to the alleged murder of the child, the military judge committed prejudicial error in denying the accused’s mistrial motion based on the inadmissible testimony of an expert witness who testified that the death was a homicide and that the accused was the perpetrator, where the expert was the key prosecution witness, where there was a related error in the admission of an earlier expert’s testimony, where the military judge’s curative instruction was inadequate and confusing, where the government’s case rested on circumstantial evidence, and where evidence of uncharged misconduct was improperly admitted
5. with regard to the alleged aggravated assault by intentionally burning, the military judge committed prejudicial error in denying the accused’s mistrial motion where the prosecution of the homicide and the assault was inextricably intertwined, where an expert witness improperly identified the accused as the perpetrator of the assault, where there was the cumulative impact of the improper testimony of three expert witnesses, and where evidence of uncharged misconduct was improperly admitted
6. the R.C.M.s specifically authorize a judge to declare a mistrial as to only some of the proceedings; this Court also has sanctioned this remedy

Trial Stages: Appeals: Standards of Review, Burdens, etc.

1. this Court will not reverse the military judge’s decision on a motion for mistrial absent clear evidence of abuse of discretion
2. when an error impacts appellant’s constitutional rights, an appellate court cannot affirm the findings unless it determines beyond a reasonable doubt that the error did not contribute to the findings of guilty; the focus is not on whether the members were right in their findings but, rather, on whether the error had or reasonably may have had an effect upon the members’ findings
3. the government bears the burden of establishing that constitutional error is harmless beyond a reasonable doubt; the appellate court examines all the circumstances to determine whether the error was harmless beyond a reasonable doubt
4. whether a constitutional error in admitting evidence is harmless beyond a reasonable doubt is a question of law that will be reviewed de novo