October Term 2023 · Docket 23-14
Can experts testify that a defendant fits a criminal profile?
The dispute centers on whether Rule 704(b) bars expert testimony that a defendant shares traits with a criminal class.
Verified source milestones
- — An official oral-argument transcript was verified.
- — An official oral-argument transcript was verified.
- — An official Court opinion was verified.
The arguments, in order
This case may have been argued more than once. Each entry below uses that session's official transcript. Later arguments do not erase earlier ones.
Argument 1 ·
What happened at the argument
Mr. Fisher argued the government does not defend the Ninth Circuit's specific rule.
Mr. Guarnieri argued the rule's text limits its application to explicit mental state opinions.
questions_and_answers
Read the official transcript for this argument · Official argument details
Sources used for this argument breakdown
- Official Supreme Court Transcript — file page 102, lines 49-29 — Transcript, file page 102, lines 49-29
- Official Supreme Court Transcript — file page 11, lines 49-17 — Transcript, file page 11, lines 49-17
- Official Supreme Court Transcript — file page 12, lines 21-29 — Transcript, file page 12, lines 21-29
- Official Supreme Court Transcript — file page 12, lines 33-35 — Transcript, file page 12, lines 33-35
- Official Supreme Court Transcript — file page 13, lines 31-43 — Transcript, file page 13, lines 31-43
- Official Supreme Court Transcript — file page 13, lines 53-1 — Transcript, file page 13, lines 53-1
- Official Supreme Court Transcript — file page 14, lines 19-37 — Transcript, file page 14, lines 19-37
- Official Supreme Court Transcript — file page 14, lines 47-51 — Transcript, file page 14, lines 47-51
- Official Supreme Court Transcript — file page 4, lines 11-21 — Transcript, file page 4, lines 11-21
- Official Supreme Court Transcript — file page 4, lines 23-41 — Transcript, file page 4, lines 23-41
- Official Supreme Court Transcript — file page 57, lines 39-33 — Transcript, file page 57, lines 39-33
- Official Supreme Court Transcript — file page 6, lines 43-7 — Transcript, file page 6, lines 43-7
- Official Supreme Court Transcript — file page 7, lines 19-27 — Transcript, file page 7, lines 19-27
- Official Supreme Court Transcript — file page 70, lines 17-53 — Transcript, file page 70, lines 17-53
- Official Supreme Court Transcript — file page 72, lines 55-27 — Transcript, file page 72, lines 55-27
- Official Supreme Court Transcript — file page 73, lines 37-41 — Transcript, file page 73, lines 37-41
- Official Supreme Court Transcript — file page 74, lines 33-29 — Transcript, file page 74, lines 33-29
- Official Supreme Court Transcript — file page 76, lines 15-45 — Transcript, file page 76, lines 15-45
- Official Supreme Court Transcript — file page 77, lines 17-37 — Transcript, file page 77, lines 17-37
- Official Supreme Court Transcript — file page 77, lines 51-1 — Transcript, file page 77, lines 51-1
- Official Supreme Court Transcript — file page 77, lines 9-11 — Transcript, file page 77, lines 9-11
- Official Supreme Court Transcript — file page 78, lines 53-13 — Transcript, file page 78, lines 53-13
- Official Supreme Court Transcript — file page 79, lines 17-23 — Transcript, file page 79, lines 17-23
- Official Supreme Court Transcript — file page 79, lines 41-9 — Transcript, file page 79, lines 41-9
- Official Supreme Court Transcript — file page 8, lines 45-51 — Transcript, file page 8, lines 45-51
- Official Supreme Court Transcript — file page 80, lines 29-51 — Transcript, file page 80, lines 29-51
- Official Supreme Court Transcript — file page 82, lines 9-25 — Transcript, file page 82, lines 9-25
- Official Supreme Court Transcript — file page 84, lines 33-37 — Transcript, file page 84, lines 33-37
- Official Supreme Court Transcript — file page 9, lines 43-49 — Transcript, file page 9, lines 43-49
- Official Supreme Court Transcript — file page 9, lines 53-43 — Transcript, file page 9, lines 53-43
A citizen's guide to the whole case
What this case is about
This case tests the scope of Federal Rule of Evidence 704(b). The rule restricts expert opinions on a defendant's mental state. The parties disagree on whether this ban covers general class-based testimony.
Official sources for this section
- Official Supreme Court Transcript — file page 102, lines 49-29 — Transcript, file page 102, lines 49-29
- Official Supreme Court Transcript — file page 4, lines 23-41 — Transcript, file page 4, lines 23-41
- Official Supreme Court Transcript — file page 57, lines 39-33 — Transcript, file page 57, lines 39-33
- Official Supreme Court Transcript — file page 70, lines 17-53 — Transcript, file page 70, lines 17-53
How the case got here
The Supreme Court heard oral argument in this case on March 19, 2024.
Official sources for this section
- Official Supreme Court Transcript — file page 4, lines 11-21 — Transcript, file page 4, lines 11-21
- Official Supreme Court Transcript — file page 77, lines 9-11 — Transcript, file page 77, lines 9-11
What each side wants
the side that brought the case wants the Court to reject the Ninth Circuit's narrow reading of Rule 704(b).
The government wants the Court to uphold the rule's plain text limitation.
Official sources for this section
- Official Supreme Court Transcript — file page 102, lines 49-29 — Transcript, file page 102, lines 49-29
- Official Supreme Court Transcript — file page 4, lines 23-41 — Transcript, file page 4, lines 23-41
- Official Supreme Court Transcript — file page 57, lines 39-33 — Transcript, file page 57, lines 39-33
- Official Supreme Court Transcript — file page 70, lines 17-53 — Transcript, file page 70, lines 17-53
What each side says
the side that brought the case argues the rule bars any testimony allowing a jury to infer the defendant's mental state.
The government argues the rule only applies when experts explicitly opine on the defendant's own mental state.
Official sources for this section
- Official Supreme Court Transcript — file page 102, lines 49-29 — Transcript, file page 102, lines 49-29
- Official Supreme Court Transcript — file page 4, lines 23-41 — Transcript, file page 4, lines 23-41
- Official Supreme Court Transcript — file page 57, lines 39-33 — Transcript, file page 57, lines 39-33
- Official Supreme Court Transcript — file page 70, lines 17-53 — Transcript, file page 70, lines 17-53
What the justices asked
Chief Justice Roberts asked if experts could clarify their testimony after testifying.
Justice Alito asked where the side that brought the case draws the line on barred inferences.
Official sources for this section
- Official Supreme Court Transcript — file page 11, lines 49-17 — Transcript, file page 11, lines 49-17
- Official Supreme Court Transcript — file page 12, lines 21-29 — Transcript, file page 12, lines 21-29
- Official Supreme Court Transcript — file page 12, lines 33-35 — Transcript, file page 12, lines 33-35
- Official Supreme Court Transcript — file page 13, lines 31-43 — Transcript, file page 13, lines 31-43
- Official Supreme Court Transcript — file page 13, lines 53-1 — Transcript, file page 13, lines 53-1
- Official Supreme Court Transcript — file page 14, lines 19-37 — Transcript, file page 14, lines 19-37
- Official Supreme Court Transcript — file page 14, lines 47-51 — Transcript, file page 14, lines 47-51
- Official Supreme Court Transcript — file page 6, lines 43-7 — Transcript, file page 6, lines 43-7
- Official Supreme Court Transcript — file page 7, lines 19-27 — Transcript, file page 7, lines 19-27
- Official Supreme Court Transcript — file page 72, lines 55-27 — Transcript, file page 72, lines 55-27
- Official Supreme Court Transcript — file page 73, lines 37-41 — Transcript, file page 73, lines 37-41
- Official Supreme Court Transcript — file page 74, lines 33-29 — Transcript, file page 74, lines 33-29
- Official Supreme Court Transcript — file page 76, lines 15-45 — Transcript, file page 76, lines 15-45
- Official Supreme Court Transcript — file page 77, lines 17-37 — Transcript, file page 77, lines 17-37
- Official Supreme Court Transcript — file page 77, lines 51-1 — Transcript, file page 77, lines 51-1
- Official Supreme Court Transcript — file page 78, lines 53-13 — Transcript, file page 78, lines 53-13
- Official Supreme Court Transcript — file page 79, lines 17-23 — Transcript, file page 79, lines 17-23
- Official Supreme Court Transcript — file page 79, lines 41-9 — Transcript, file page 79, lines 41-9
- Official Supreme Court Transcript — file page 8, lines 45-51 — Transcript, file page 8, lines 45-51
- Official Supreme Court Transcript — file page 80, lines 29-51 — Transcript, file page 80, lines 29-51
- Official Supreme Court Transcript — file page 82, lines 9-25 — Transcript, file page 82, lines 9-25
- Official Supreme Court Transcript — file page 84, lines 33-37 — Transcript, file page 84, lines 33-37
- Official Supreme Court Transcript — file page 9, lines 43-49 — Transcript, file page 9, lines 43-49
- Official Supreme Court Transcript — file page 9, lines 53-43 — Transcript, file page 9, lines 53-43
Why it matters
This case defines the boundary of expert testimony in criminal trials. It determines whether juries can hear general class-based opinions. The outcome shapes how experts present evidence about defendant behavior.
Official sources for this section
- Official Supreme Court Transcript — file page 102, lines 49-29 — Transcript, file page 102, lines 49-29
- Official Supreme Court Transcript — file page 4, lines 23-41 — Transcript, file page 4, lines 23-41
- Official Supreme Court Transcript — file page 57, lines 39-33 — Transcript, file page 57, lines 39-33
- Official Supreme Court Transcript — file page 70, lines 17-53 — Transcript, file page 70, lines 17-53
What happens next
This article currently covers the argument record. Use the official docket link for later case activity.
Official sources for this section
- Official Supreme Court Transcript — file page 11, lines 49-17 — Transcript, file page 11, lines 49-17
- Official Supreme Court Transcript — file page 12, lines 21-29 — Transcript, file page 12, lines 21-29
- Official Supreme Court Transcript — file page 12, lines 33-35 — Transcript, file page 12, lines 33-35
- Official Supreme Court Transcript — file page 13, lines 31-43 — Transcript, file page 13, lines 31-43
- Official Supreme Court Transcript — file page 13, lines 53-1 — Transcript, file page 13, lines 53-1
- Official Supreme Court Transcript — file page 14, lines 19-37 — Transcript, file page 14, lines 19-37
- Official Supreme Court Transcript — file page 14, lines 47-51 — Transcript, file page 14, lines 47-51
- Official Supreme Court Transcript — file page 4, lines 11-21 — Transcript, file page 4, lines 11-21
- Official Supreme Court Transcript — file page 6, lines 43-7 — Transcript, file page 6, lines 43-7
- Official Supreme Court Transcript — file page 7, lines 19-27 — Transcript, file page 7, lines 19-27
- Official Supreme Court Transcript — file page 72, lines 55-27 — Transcript, file page 72, lines 55-27
- Official Supreme Court Transcript — file page 73, lines 37-41 — Transcript, file page 73, lines 37-41
- Official Supreme Court Transcript — file page 74, lines 33-29 — Transcript, file page 74, lines 33-29
- Official Supreme Court Transcript — file page 76, lines 15-45 — Transcript, file page 76, lines 15-45
- Official Supreme Court Transcript — file page 77, lines 17-37 — Transcript, file page 77, lines 17-37
- Official Supreme Court Transcript — file page 77, lines 51-1 — Transcript, file page 77, lines 51-1
- Official Supreme Court Transcript — file page 77, lines 9-11 — Transcript, file page 77, lines 9-11
- Official Supreme Court Transcript — file page 78, lines 53-13 — Transcript, file page 78, lines 53-13
- Official Supreme Court Transcript — file page 79, lines 17-23 — Transcript, file page 79, lines 17-23
- Official Supreme Court Transcript — file page 79, lines 41-9 — Transcript, file page 79, lines 41-9
- Official Supreme Court Transcript — file page 8, lines 45-51 — Transcript, file page 8, lines 45-51
- Official Supreme Court Transcript — file page 80, lines 29-51 — Transcript, file page 80, lines 29-51
- Official Supreme Court Transcript — file page 82, lines 9-25 — Transcript, file page 82, lines 9-25
- Official Supreme Court Transcript — file page 84, lines 33-37 — Transcript, file page 84, lines 33-37
- Official Supreme Court Transcript — file page 9, lines 43-49 — Transcript, file page 9, lines 43-49
- Official Supreme Court Transcript — file page 9, lines 53-43 — Transcript, file page 9, lines 53-43
Official Court provenance
Official docket and case history · Official Supreme Court oral-argument detail page
Verified official opinions and orders
Title and summary sources
- Official Supreme Court Transcript — file page 102, lines 49-29 — Transcript, file page 102, lines 49-29
- Official Supreme Court Transcript — file page 4, lines 23-41 — Transcript, file page 4, lines 23-41
- Official Supreme Court Transcript — file page 57, lines 39-33 — Transcript, file page 57, lines 39-33
- Official Supreme Court Transcript — file page 70, lines 17-53 — Transcript, file page 70, lines 17-53
- Official Supreme Court Transcript — file page 102, lines 49-29 — Transcript, file page 102, lines 49-29
- Official Supreme Court Transcript — file page 4, lines 23-41 — Transcript, file page 4, lines 23-41
- Official Supreme Court Transcript — file page 57, lines 39-33 — Transcript, file page 57, lines 39-33
- Official Supreme Court Transcript — file page 70, lines 17-53 — Transcript, file page 70, lines 17-53
Revision history
- Revision 1 · Post Opinion ·
Correction: Rewritten to the concise citizen-facing editorial standard.
- Revision 2 · Post Opinion ·
Correction: Migrated to the dated official Court activity contract without model use.