I don’t know about every state in the U.S., but unless things have changed since I left in 2001, the results of a polygraph test are not admissible in a criminal proceeding in a Louisiana state trial court.
And as to federal (i.e., national) courts, the quote below is from my recollection of a trial transcript of a criminal proceeding in a U.S. federal court, so it may not be 100% accurate (especially as to the precise order or sequence of the speakers), but I believe it’s accurate in its essentials:
[quote]Prosecutor: Did you take a lie-detector test?
Defense Counsel: Your Honor?
Prosecutor: What were the results?
Defense Counsel: Your Honor, polygraph.
Witness: I passed.
[At this point, I think the jury was sent out.]
Judge: Well, looks like that horse done got out the barn.[/quote]
I wasn’t there, so I don’t know if defense counsel was too slow in objecting (defense counsel was able counsel, by the way, especially at trial) or the judge was distracted (the judge was quite smart, his occasional use of folksy language notwithstanding), or if the Assistant U.S. Attorney asked the question very rapidly so that it could be answered before an objection could be properly raised and sustained, but the point is that even though the Assistant U.S. Attorney pulled a fast one and got away with it, it was clearly inadmissible.
Whoa, just call me Jethro, and I’ll back up the truck. Apologies, HGC. I may well be wrong about federal court. I seem to have been right about Louisiana, though:
[quote]This Court has long adhered to the view that lie detector or polygraph test results are inadmissible for any purpose at the trial of guilt or innocence in criminal cases. Consistent with this view, the Court has made it clear that the rule excluding polygraph evidence “also operates to prevent any reference during trial to the fact that a witness has taken a polygraph examination with respect to the subject matter of his testimony.” State v. Hocum, 456 So.2d 602, 604 (La. 1984); State v. Tonnubee, 420 So.2d 126, 132 (La. 1982 ), cert. denied, 46 U.S. 1146, 103 S.Ct. 1768, 76 L. Ed. 2d 342 (1983); State v. Davis, 407 So.2d 702, 706 (La. 1981); State v. Cantanese, 368 97-2020.KA1 16So.2d 975, 981 (La. 1979). Such evidence is prohibited because it “invites a probable inference by the jury that the witness passed the polygraph examination and therefore is testifying truthfully.” Hocum, 420 So.2d t 604-605. Therefore, the trial court correctly ruled that no evidence of the polygraph results was admissible at trial.[/quote]–State v. Cosey (Louisiana Supreme Court, 2000) lasc.org/opinions/2000/97ka2020.opn.pdf (PDF document)
Caveat: But I could be wrong about Louisiana, too. The above case is more than nine years old. The (judge-made) law may have changed in Louisiana since then.
I need to do some more rooting around. Dang, I’m about to risk getting fired for disputing the casual musings of an antipodian somewhere out in the aether! And to top it off, it looks like I’m losing the dispute!
HGC, It turns out that you are essentially correct and I am essentially wrong as to federal court. It’s a mixed bag. Here’s a summary of some cases (notes: the commentator mentions Daubert, a U.S. Supreme Court case which set standards for the admissibility of scientific evidence based apparently on Rule 702 of the Federal Rules of Evidence–citations have been omitted–asterisks indicate sizeable snipping):
[quote]In United States v. Posado, the Fifth Circuit . . . held that polygraph evidence would be not be per se inadmissible under Daubert. The court viewed polygraph testing favorably and decided to allow polygraph evidence “in certain circumstances.”
Another federal court, however, reached the opposite conclusion regarding polygraph evidence. The Eastern District of New York decided that “polygraph evidence is neither reliable nor admissible” under Daubert.
In a third case, the Southern District of New York failed to rule on the admissibility of polygraph evidence under Daubert and Rule 702, but instead excluded the polygraph evidence as misleading and confusing to the jury under Rule 403.
The Sixth Circuit took a similar route in another polygraph case and excluded the polygraph test results under Rule 403.
Finally, adopting a middle ground, the U.S. Court of Military Appeals ruled that because the greater weight of authority indicates that polygraph examinations can be a helpful scientific tool, polygraph evidence can neither be accepted nor rejected out of hand.
- *[/quote]–Jay P. Kesan, Ph.D., “A Critical Examination of the Post-Daubert Scientific Evidence Landscape,” 52 Food & Drug L.J. 225 (1997) (taken from Georgetown University Law Center’s Web Pages at law.georgetown.edu/faculty/c … kesan.html )
As to Louisiana case law, I’m afraid to look any further. Bested by an Aussie about my own country’s laws! But at least I haven’t been fired yet. They startin to look at me funny, though.