                FOR PUBLICATION

  UNITED STATES COURT OF APPEALS
       FOR THE NINTH CIRCUIT


UNITED STATES OF AMERICA,                     No. 18-50115
               Plaintiff-Appellee,
                                                D.C. No.
                v.                          17-CR-00159-PA-2

DANIEL RAY, AKA Popeye, AKA
Daniel T. Ray, AKA Daniel
Thomas Ray,
             Defendant-Appellant.


UNITED STATES OF AMERICA,                     No. 18-50120
               Plaintiff-Appellee,
                                                D.C. No.
                v.                          17-CR-00159-PA-1

PATRICK JOHN BACON,
            Defendant-Appellant.               OPINION

      Appeal from the United States District Court
         for the Central District of California
       Percy Anderson, District Judge, Presiding

         Argued and Submitted January 6, 2020
                 Pasadena, California

                     Filed April 28, 2020
2                    UNITED STATES V. RAY

    Before: Paul J. Watford and Mark J. Bennett, Circuit
        Judges, and Jed S. Rakoff, * District Judge.

                    Per Curiam Opinion;
                Concurrence by Judge Watford


                          SUMMARY **


                          Criminal Law

    The panel vacated a conviction for assault with a deadly
weapon with intent to do bodily harm and assault causing
serious bodily injury, and remanded for a new trial, in a case
in which Patrick Bacon argued that the district court should
have allowed his forensic clinical expert psychologist to
testify, which would have allowed Bacon to present his
insanity defense to the jury.

    The panel wrote that the psychologist’s report
demonstrates that his evaluation of Bacon was relevant to
Bacon’s insanity defense, and that the district court therefore
abused its discretion by excluding the psychologist’s
testimony on the ground that the psychologist did not opine
that Bacon was unable to appreciate the nature and quality
of his acts at the time of the assault. The panel wrote that
this was the wrong legal standard. Instead, the district court
should have focused on whether the testimony would have

    *
     The Honorable Jed S. Rakoff, United States District Judge for the
Southern District of New York, sitting by designation.
    **
       This summary constitutes no part of the opinion of the court. It
has been prepared by court staff for the convenience of the reader.
                   UNITED STATES V. RAY                       3

assisted the jury in drawing its own conclusion as to a fact
issue—the impact of any serious mental health disease or
defect on Bacon’s ability to appreciate the nature and quality
of his acts. The panel did not hold that the district court must
admit the psychologist’s testimony on remand, only that the
district court abused its discretion in finding the testimony
was not relevant to Bacon’s insanity defense. The panel
wrote that to fulfill its gatekeeping function under Fed. R.
Evid. 702 and Daubert, the district court on remand should
consider whether the psychologist’s testimony is reliable.
The panel held that the exclusion of the testimony was not
harmless because without it Bacon was unable to present his
insanity defense.

    Applying United States v. Christian, 749 F.3d 806 (9th
Cir. 2014), and Baabin v. AstenJohnson, Inc., 740 F.3d 457
(9th Cir. 2014) (en banc), the panel wrote that it was bound
to vacate the conviction and remand for a new trial.

    Concurring, Judge Watford, joined by Judges Bennett
and Rakoff, wrote separately to highlight how wasteful of
judicial resources the remedy of remanding for a new trial
potentially is.

    In a concurrently filed memorandum disposition, the
panel resolved remaining issues in Bacon’s and Daniel Ray’s
cases.
4                   UNITED STATES V. RAY

                           COUNSEL

Ethan A. Balogh (argued), Dejan M. Gantar, and Narai
Sugino, Coleman & Balogh LLP, San Francisco, California,
for Defendant-Appellant Daniel Ray.

Shaun Khojayan (argued), Law Offices of Shaun Khojayan
& Associates P.L.C., Los Angeles, California, for
Defendant-Appellant Patrick John Bacon.

Shawn T. Andrews (argued) and Bram M. Alden, Assistant
United States Attorneys; L. Ashley Aull, Chief, Criminal
Appeals Section; Nicola T. Hanna, United States Attorney;
United States Attorney’s Office, Los Angeles, California;
for Plaintiff-Appellee.


                           OPINION

PER CURIAM:

    Patrick Bacon and Daniel Ray were convicted of assault
with a deadly weapon with intent to do bodily harm and
assault causing serious bodily injury. 18 U.S.C. § 113(a)(3),
(6). They were sentenced to 120 months and 100 months,
respectively. On appeal Bacon argues that the district court
should have allowed his forensic clinical expert
psychologist, Dr. Karim, to testify, which would have
allowed him to present his insanity defense to the jury. We
hold that the district court abused its discretion in excluding
Dr. Karim’s testimony because the testimony was relevant
to Bacon’s defense. 1 Because this error was not harmless,

    1
      In a concurrently filed memorandum disposition, we resolve the
remaining issues in the case.
                      UNITED STATES V. RAY                               5

and we cannot tell from the record whether the testimony
was reliable, we must vacate Bacon’s conviction and remand
for a new trial. 2

                                    I.

   Bacon and Ray were both incarcerated at Victorville
Federal Prison in California. Bacon stabbed inmate Anthony
Grecco with a metal shank, fracturing Grecco’s sinus cavity
and causing stab wounds to his head and chest. Security
cameras recorded the attack and events beforehand.

    Bacon had entered a housing unit, and when questioned
by correctional officers, lied and said he was housed there.
He met with Ray, and they both walked to Ray’s cell. Ray
took a book from the cell. Defendants walked to a table,
where Ray put the book in front of Bacon and walked away.
Bacon took the book apart. Ray returned and stood next to
Bacon, until Bacon left holding something below his waist.
Bacon then stabbed Grecco with the shank. Guards
responded, broke up the assault, and recovered the shank and
book.

    A grand jury indicted Bacon and Ray under 18 U.S.C.
§ 113(a)(3) (assault with a deadly weapon with intent to do
bodily harm) and (a)(6) (assault causing serious bodily


    2
      We deny Bacon’s request to assign this case to a different district
court judge on remand. The record does not show that the district judge
was biased or that other unusual circumstances were present. See United
States v. Peyton, 353 F.3d 1080, 1091 (9th Cir. 2003), overruled on other
grounds by United States v. Contreras, 593 F.3d 1135, 1136 (9th Cir.
2010) (en banc); see also Liteky v. United States, 510 U.S. 540, 555
(1994) (“[J]udicial rulings alone almost never constitute a valid basis for
a bias or partiality motion.”).
6                 UNITED STATES V. RAY

injury). After a two-day trial, a jury found defendants guilty
of both counts.

    Prior to trial Bacon gave notice, pursuant to Federal Rule
of Criminal Procedure 12.2, that he would assert an insanity
defense. The government then moved in limine to preclude
Bacon’s expert, Dr. Karim. Among other conclusions,
Dr. Karim opined: (1) “that a review of Mr. Bacon’s
psychosocial history confirms that he has suffered from a
severe and chronic mental illness (or defect) throughout the
course of his adult life” and “he presents with long-standing
and chronic mental health disorders”; (2) “there are elements
of a downward spiral of isolation, depression, paranoia, and
anxiety that resulted in a dissociative state for Mr. Bacon
prior to the conduct itself” and (3) as a result “it would be
reasonable to conclude with a high degree of clinical
certainty that an individual who was suffering from the
myriad of severe mental health disorders that Mr. Bacon was
facing on October 18, 2016 would have had difficulty
understanding the nature and quality of his actions at the
time of the offense conduct.” Dr. Karim acknowledged that
Bacon has “a history of aggression and physical assaults,”
but concluded that Bacon’s psychological deterioration
during the months before the assault impacted his ability to
“differentiate his actions” at the time of the assault.
Dr. Karim further suggested that Bacon’s “largely
unplanned and unsophisticated criminal history” could be
explained by “a diagnosis of an Unspecified Bipolar
disorder.”

    The government moved to preclude Dr. Karim’s
testimony. The government argued the expert testimony was
irrelevant and unreliable under Daubert and Federal Rule of
Evidence 702, because Dr. Karim did not opine that Bacon
suffered from “any mental health disorder” on the date of the
                      UNITED STATES V. RAY                             7

assault, his opinion about a “dissociative state” was not
based on medical literature, he did not explain the results of
tests he administered to Bacon, and his opinions appeared to
have been based on hearsay.

    The district court granted the motion, finding that under
Rule 702, Dr. Karim’s opinion was not relevant because it
would “not help the trier of fact to understand the evidence
or determine the issue of sanity.” After explaining the
Daubert and Rule 702 standards, and summarizing
Dr. Karim’s opinions, the district court stated: “We start
with the question of relevance. In fact, we start and end with
the question of relevance.” The court found that
“Dr. Karim’s opinion that an individual who was suffering
from a myriad of severe mental health disorders that Mr.
Bacon was facing would have had difficulty understanding
the nature and quality of his action at the time of the offense
conduct is equivocal and will not help the trier of fact to
understand the evidence or determine the issue of sanity.”
The court also stated that Dr. Karim’s testimony does “not
satisfy the threshold standard of relevance” because
“Dr. Karim is unwilling or cannot opine that as a result of
Mr. Bacon’s mental health issues he was unable, as opposed
to [had] difficulty understanding, [or] appreciat[ing] the
nature and quality of his acts . . . .” Thus, according to the
district court, Dr. Karim’s testimony did not “satisfy the
standard to entitle the defendant to [assert] an insanity
defense according to the law of this circuit.” 3 The court
ultimately found “that Dr. Karim’s opinions, therefore, are
speculative, irrelevant, and unreliable.”



     3
       The district court also noted that “Dr. Karim’s opinions, in part,
violate 704.”
8                    UNITED STATES V. RAY

     In the alternative, the district court found that “Dr. Karim
is precluded from testifying as an expert witness because
whatever probative value the proffered testimony may have
[is] substantially outweighed by undue prejudice, confusion
of the issues, and undue waste of time under [Federal Rule
of Evidence] 403.” 4 Because the district court precluded
Dr. Karim from testifying, it barred Bacon’s insanity
defense, under 18 U.S.C. § 17, the Insanity Defense Reform
Act (“IDRA”). 5

    We have jurisdiction under 28 U.S.C. § 1291.

                                 II.

    We review “the district court’s exclusion of expert
testimony” for abuse of discretion. United States v.
Christian, 749 F.3d 806, 810 (9th Cir. 2014). We first
“consider whether the district court identified the correct
legal standard for decision of the issue before it” and then
we “determine whether the district court’s findings of fact,
and its application of those findings of fact to the correct
legal standard, were illogical, implausible, or without
support in inferences that may be drawn from facts in the
record.” United States v. Hinkson, 585 F.3d 1247, 1251 (9th
Cir. 2009) (en banc).


    4
      Bacon timely objected to the district court’s ruling precluding
Dr. Karim from testifying.

    5
       The IDRA requires the defendant, by clear and convincing
evidence, to prove that “he suffered from a serious mental disease or
defect at the time of the crime” and that “his mental disease or defect
must have prevented him from appreciating the nature and quality or
wrongfulness of his acts.” United States v. Knott, 894 F.2d 1119, 1121
(9th Cir. 1990).
                       UNITED STATES V. RAY                                 9

                                     A.

    Bacon argues that the district court abused its discretion
by refusing to allow Dr. Karim’s testimony even though it
was relevant and reliable. “The admissibility of expert
testimony is generally governed by Federal Rule of Evidence
702, which requires district courts to ‘perform a gatekeeping
function to ensure that the expert’s proffered testimony is
both reliable and relevant.’” Christian, 749 F.3d at 810
(quoting United States v. Redlightning, 624 F.3d 1090, 1111
(9th Cir. 2010)). Here the district court focused exclusively
on relevance when evaluating Dr. Karim’s testimony: “We
start with the question of relevance. In fact, we start and end
with the question of relevance.” 6

    The correct legal standard is for the district court “to
determine the relevance of the psychological evaluation the
expert conducted and the medical diagnoses he made, not his
ultimate legal conclusion regarding the defendant’s mental
state.” Christian, 749 F.3d at 811. Here, the district court
instead focused on Dr. Karim’s bottom-line opinions, rather
than “his proposed expert testimony,” id., contrary to our
guidance in Christian. There, we emphasized “that a district
court deciding whether to admit expert testimony should
evaluate whether that testimony ‘will assist the trier of fact
in drawing its own conclusion as to a fact in issue’ and
should not limit its consideration to ‘the existence or strength
of an expert’s opinion.’” Id. (quoting United States v. Rahm,
993 F.2d 1405, 1411 (9th Cir. 1993)). We explained this is
necessary because the doctor there could not have testified

    6
        While the district court did conclude that “Dr. Karim’s opinions
. . . are speculative, irrelevant, and unreliable,” the court’s analysis under
Rule 702 focused exclusively on relevance and did not consider
reliability at all.
10                  UNITED STATES V. RAY

that the defendant “lacked the capacity to form the specific
intent to threaten,” id. at 812 (citing Fed. R. Evid. 704(b)),
and “[i]t would make little sense to require a conclusive
opinion in determining admissibility, and then absolutely to
forbid expression of the opinion in testimony,” id. (quoting
Rahm, 993 F.2d at 1411 n.3). So too here. Dr. Karim could
not have testified to the jury that Bacon’s mental disease and
defect prevented him from appreciating the nature and
quality or wrongfulness of his acts, because “an expert
witness must not state an opinion about whether the
defendant did or did not have a mental state or condition that
constitutes an element of the crime charged or of a defense.”
Fed. R. Evid. 704(b). Thus “the absence of an opinion to that
effect in his report is not a valid reason to preclude his
testimony.” Christian, 749 F.3d at 812.

    Dr. Karim’s report demonstrates that his evaluation of
Bacon was relevant to Bacon’s insanity defense. For
example, Dr. Karim concluded that Bacon “was suffering
from a myriad of severe mental health disorders,” and that
Bacon “would have had difficulty understanding the nature
and quality of his actions at the time of the offense conduct.”
If admissible, testimony about these “severe” mental health
disorders and their impact on Bacon’s perception at the time
of the assault “may well have been helpful to the jury in
deciding,” Christian, 749 F.3d at 812, whether Bacon was
insane at the time.

    Accordingly, the district court abused its discretion by
precluding Dr. Karim’s testimony because he did not opine
that Bacon was unable to appreciate the nature and quality
of his acts at the time of the assault. 7 This was the wrong

     7
      To the extent the district court ruled that Rule 704 precluded
Dr. Karim from testifying, it abused its discretion. See Christian,
                     UNITED STATES V. RAY                         11

legal standard. Instead, the district court should have focused
on whether Dr. Karim’s testimony would have assisted the
jury “in drawing its own conclusion as to a ‘fact in issue,’”
id. at 811—the impact of any serious mental health disease
or defect on Bacon’s ability to appreciate the nature and
quality of his acts.

    If otherwise admissible, Dr. Karim’s expert testimony
“would have been highly probative” of Bacon’s mental state
and “unlikely to cause significant confusion with the jury if
properly constrained by compliance with the rules of
evidence.” United States v. Cohen, 510 F.3d 1114, 1126–27
(9th Cir. 2007). Thus, even if the district court had explained
the Rule 403 exclusion, it likely would have abused its
discretion. With no explanation, it clearly did so.

     We do not hold that the district court must admit
Dr. Karim’s testimony on remand, only that the district court
abused its discretion in finding the testimony was not
relevant to Bacon’s insanity defense. On remand, to fulfill
its “gatekeeping function” under Rule 702 and Daubert, the
district court should consider whether Dr. Karim’s testimony
is reliable. See Christian, 749 F.3d at 810 (quoting
Redlightning, 624 F.3d at 1111). The government, in its
Daubert motion, raised a number of very real reliability
issues with Dr. Karim’s expert testimony, including that
Dr. Karim did not explain his reasoning or methodology in
arriving at his conclusions and cited no medical literature
showing that a “dissociative state” or other mental health
disorders suffered by Bacon at the time of the offense are
considered mental diseases or defects. We cannot express
any view on the admissibility of Dr Karim’s testimony under

749 F.3d at 812 n.2 (Rule 704(b) “limit[s] the scope of [an expert’s]
testimony” but does not “prohibit[] him from testifying at all.”).
12                   UNITED STATES V. RAY

Rule 702 “because the record before us is too sparse to
determine whether the expert testimony is . . . reliable.”
Barabin v. AstenJohnson, Inc., 740 F.3d 457, 466 (9th Cir.
2014) (en banc).

                                  B.

    We must decide whether the exclusion of Dr. Karim’s
testimony was harmless error. See United States v. Morales,
108 F.3d 1031, 1040 (9th Cir. 1997) (en banc). It was not. If
the district court had admitted Dr. Karim’s testimony,
Bacon’s insanity defense would have gone to the jury. Given
Bacon’s prior mental health diagnoses, an expert witness
may have “provided some evidentiary basis for inferring . . .
a link between [Bacon’s] obvious mental illness and [his]
sole defense.” Christian, 749 F.3d at 813. Without this
testimony Bacon was unable to present his insanity defense
to the jury. Thus, the error was not harmless, and Bacon’s
“substantial rights were affected by the district court’s
error.” 8 Id.; see also Rahm, 993 F.2d at 1415–16.

                                 III.

    We now turn to the proper remedy for the district court’s
non-harmless error of precluding Bacon’s expert testimony:
We must vacate the conviction and remand for a new trial.
See Christian, 749 F.3d at 814. In Christian, we explained
that “Barabin extended a general evidentiary rule requiring
a new trial ‘[w]hen the district court has erroneously
admitted or excluded prejudicial evidence’ to the admission
of expert testimony.” Id. (quoting Barabin, 740 F.3d at 466
     8
       We do not reach Bacon’s challenge that excluding Dr. Karim’s
testimony violated Bacon’s constitutional right to present a defense
because we “reverse on the basis of the nonconstitutional evidentiary
error.” United States v. Rahm, 993 F.2d 1405, 1416 n.6 (9th Cir. 1993).
                      UNITED STATES V. RAY                           13

(alteration in original)). While acknowledging that “Barabin
involved the admission of expert testimony in a civil trial,”
the Christian court held “that Barabin’s analysis applies
with equal force to” criminal cases in which the district court
excluded expert testimony. Id. Absent intervening Supreme
Court authority, we are bound by the prior decisions of this
Court. See Miller v. Gammie, 335 F.3d 889, 893, 899–900
(9th Cir. 2003) (en banc). Accordingly, we vacate Bacon’s
conviction and remand for a new trial. 9

    VACATED and REMANDED.



WATFORD, Circuit Judge, joined by BENNETT, Circuit
Judge, and RAKOFF, District Judge, concurring:

    I agree with my colleagues that circuit precedent requires
us to remand this case to the district court for a new trial. See
United States v. Christian, 749 F.3d 806, 813–14 (9th Cir.
    9
       We note two issues that may arise again on remand. First, if
Bacon’s insanity defense goes to the jury, his father’s lay testimony
about Bacon’s mental health history would not be per se irrelevant even
if the proffered testimony goes to events that occurred several years
before the assault. See, e.g., Crawford v. City of Bakersfield, 944 F.3d
1070, 1079 (9th Cir. 2019) (finding under Rule 701 that as long as a
mother “stopped short of opining that [the son] had a mental illness, she
was competent to testify about her own observations of and experiences
with” her son’s past behavior).

    Second, if Bacon again testifies and the government seeks to
impeach him with evidence of his prior convictions, the district court
should consider the five factors we noted in United States v. Hursh,
217 F.3d 761 (9th Cir. 2000), when “balancing the probative value of
evidence of a defendant’s prior convictions against that evidence’s
prejudicial effect,” id. at 768. We express no view on the merits of any
challenges to that impeachment.
14                 UNITED STATES V. RAY

2014); Estate of Barabin v. AstenJohnson, Inc., 740 F.3d
457, 466–67 (9th Cir. 2014) (en banc). I write separately to
highlight how wasteful of judicial resources that remedy
potentially is. See Estate of Barabin, 740 F.3d at 469
(Nguyen, J., concurring in part and dissenting in part).

    Our panel does not hold that Dr. Karim’s testimony must
be admitted at the new trial. We merely hold that his
testimony may not be excluded on the ground originally
given by the district court (relevance), and we remand the
case so that the district court can assess the other grounds on
which Dr. Karim’s testimony might still be excluded, most
notably as not meeting the standard for reliability imposed
by Federal Rule of Evidence 702. See Daubert v. Merrell
Dow Pharmaceuticals, Inc., 509 U.S. 579 (1993). What if,
on remand, the district court decides that Dr. Karim’s
testimony is insufficiently reliable, and thus must be
excluded once again? If that occurs, why in the world should
the court hold a new trial at which a second jury will hear
the same evidence heard by the jury at the first trial?

    As Judge Nguyen argued in Estate of Barabin, the far
more sensible procedure would be to “conditionally vacate
the judgment and remand to the district court with
instructions to determine whether the disputed expert
testimony was admissible pursuant to the requirements of
Rule 702 and Daubert.” 740 F.3d at 471 (Nguyen, J.,
concurring in part and dissenting in part). Under that
procedure, if the court determined on remand that
Dr. Karim’s testimony is inadmissible, it would simply
reinstate the judgment. Only if the court determined that
Dr. Karim’s testimony is admissible, and therefore was
wrongly kept from the jury at the first trial, would there be a
need for a retrial. Since this eminently sensible procedure is
                   UNITED STATES V. RAY                     15

forbidden by existing circuit precedent, I reluctantly join the
court’s disposition.
