Neuroimaging and Competency to Be Executed after Panetti

40 Pages Posted: 23 Feb 2010


Scholars have begun to consider the impact of neuroimaging evidence on capital punishment trials, questioning whether reliance on such testimony can actually make “sentencing more rational and humane.” They have also considered the impact of this evidence on criminal sentencing, expressing concern that such evidence will be improperly used “as predictive factors to increase sentences,” and counseling policymakers to “avoid misuse of new techniques.” In an earlier article on neuroimaging and criminal procedure, I considered the questions of a criminal defendant’s competency to submit to neuroimaging testing, and the impact of antipsychotic medications on the results of such testing.

What has not yet been considered, to the best of my knowledge, is the potential significance of such evidence on an issue that combines aspects of these inquiries from one singular perspective: its potential impact on cases determining whether a seriously mentally disabled death row defendant is competent to be executed. In Panetti v. Quarterman (127 S. Ct. 2842 (2007)), the Supreme Court ruled that such a defendant had a constitutional right to make a showing that his mental illness “obstruct[ed] a rational understanding of the State’s reason for his execution,” expanding its jurisprudence in this area beyond its earlier decision in Ford v. Wainwright that had regularly been interpreted to require that competency-to-be-executed depended on only three findings: that the prisoner is aware he committed the murders, that he is going to be executed, and he is aware of the reasons the State has given for his execution.

Although it is too early to come to any definitive conclusions about the “real life” implementation of Panetti, we know that in many jurisdictions implementation of Ford was simply nonexistent, suggesting that fact-finders were utterly disinterested in the testimony presented at hearings designed to thwart execution in cases where it was alleged that the defendant did not meet the Ford standard. To the best of my knowledge, it does not appear that neuroimaging testimony was relied on in any of the (published) cohort of these cases.

Panetti suggests that competency-to-be-executed hearings may necessarily have to become more sophisticated and complex, especially in light of the other Panetti holding that the trial court’s failure to provide the defendant an adequate opportunity to submit expert evidence in response to the report filed by the court-appointed experts deprived him of his “constitutionally adequate opportunity to be heard.” This also leads to the question that I explore in this paper: what impact will neuroimaging testimony have on future Panetti hearings?

This question subsumes multiple sub-questions: • Will defense counsel seek to introduce such testimony, and what, exactly, can we expect such testimony will say? • In cases involving indigent defendants, will Ake v. Oklahoma be interpreted expansively or restrictively? • Will prosecutors seek to introduce such testimony to rebut defendant’s Panetti applications? • To what extent are judges more or less impervious to the “dazzle” or “Christmas tree effect” of such testimony than are jurors? • How will such testimony be dealt with if there is a Daubert challenge? • How will judges deal with such testimony in cases where the evidence revealed by neuroimaging testimony does not comport with their (false) “ordinary common sense” view of “crazy” criminal defendants?

I offer preliminary answers to all these questions in this paper.

Keywords: neuroimaging, criminal procedure, expert witness, violence, forensic testimony

Suggested Citation

Perlin, Michael L., Neuroimaging and Competency to Be Executed after Panetti. NYLS Legal Studies Research Paper No. 09/10 #20, Available at SSRN:

Michael L. Perlin (Contact Author)

New York Law School ( email )

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