956 F.3d 1154
9th Cir.2020Background
- At Victorville Federal Prison, Patrick Bacon stabbed fellow inmate Anthony Grecco; the assault was captured on security cameras.
- Bacon and co-defendant Daniel Ray were indicted and convicted of assault with a deadly weapon and assault causing serious bodily injury.
- Bacon timely asserted an insanity defense under Fed. R. Crim. P. 12.2 and proffered a forensic psychologist, Dr. Karim, whose report diagnosed severe, chronic mental illness and opined Bacon likely had difficulty understanding the nature and quality of his actions.
- The government moved in limine under Daubert and Rule 702; the district court excluded Dr. Karim’s testimony as irrelevant because he would not (and by Rule 704(b) could not) state that Bacon was unable to appreciate the nature and quality of his acts. The court also referenced Rule 403 and Rule 704.
- The Ninth Circuit held the district court applied the wrong legal standard by focusing on the expert’s ultimate legal conclusion rather than whether the expert’s evaluation would assist the jury in deciding Bacon’s sanity; the court found exclusion was an abuse of discretion and not harmless.
- Because the record is too sparse to assess reliability under Rule 702/Daubert, the Ninth Circuit vacated Bacon’s conviction and remanded for a new trial so the district court can reconsider admissibility and reliability of the expert testimony.
Issues
| Issue | Plaintiff's Argument | Defendant's Argument | Held |
|---|---|---|---|
| Admissibility of Dr. Karim’s expert testimony under Rule 702/Daubert | Govt: testimony irrelevant and unreliable because Dr. Karim did not opine Bacon lacked capacity on the offense date and methodology was unsupported | Bacon: report on diagnoses and effects was relevant and would assist jury in determining insanity; absence of a forbidden ultimate opinion is not a proper basis to exclude | Court: Exclusion was an abuse of discretion — district court applied wrong standard by focusing on ultimate legal conclusion rather than whether testimony would help jury; remand to assess reliability |
| Application of Fed. R. Evid. 704(b) (ultimate-issue testimony) | Govt: Rule 704(b) bars testimony opining defendant had the mental state constituting the defense | Bacon: expert may testify about diagnoses/effects; Rule 704(b) limits scope but does not bar testimony that assists jury | Court: Rule 704(b) does not justify preclusion here; absence of a forbidden ultimate opinion is not a valid reason to exclude testimony |
| Harmless error analysis for exclusion of expert testimony | Govt: exclusion harmless given recorded attack and other evidence | Bacon: exclusion was not harmless because expert was needed to present insanity defense to jury | Court: Error was not harmless — without expert Bacon could not present insanity defense; substantial rights affected |
| Remedy after erroneous exclusion of prejudicial expert evidence | Govt: seek to affirm conviction or limited remedy | Bacon: new trial if exclusion was prejudicial | Court: Following Ninth Circuit precedent, vacate conviction and remand for new trial; district court to reassess admissibility under Rule 702/Daubert on remand |
Key Cases Cited
- United States v. Christian, 749 F.3d 806 (9th Cir. 2014) (expert-admissibility standard: evaluate whether testimony assists jury, not the expert’s ultimate legal conclusion)
- Estate of Barabin v. AstenJohnson, Inc., 740 F.3d 457 (9th Cir. 2014) (en banc) (erroneous admission or exclusion of prejudicial expert evidence generally requires new trial)
- Daubert v. Merrell Dow Pharm., 509 U.S. 579 (1993) (establishing district court gatekeeping duties for expert reliability)
- United States v. Hinkson, 585 F.3d 1247 (9th Cir. 2009) (en banc) (standard for reviewing district court factual findings and legal standards on admissibility)
- United States v. Rahm, 993 F.2d 1405 (9th Cir. 1993) (discussion of limits on experts testifying to ultimate legal conclusions)
- United States v. Knott, 894 F.2d 1119 (9th Cir. 1990) (explaining IDRA requirements for insanity defense)