In a federal sex offender case, in what circumstances will a defense counsel be allowed to use the past convictions of a convicted sex offender as evidence in the criminal threats trial?

Defense counsel was faced with a bad hand to play regarding petitioner's past convictions. Although quite violent, they were most assuredly relevant and important with respect to the criminal threats charge. Indeed, this was the evidence, strictly limited in description, which played a large role in determining whether the spousal victim had sustained fear, and why she would have such fear. A "threat" made by someone who never exhibited violent tendencies might well be viewed by the person to whom the statement was directed as more like hyperbole, as opposed to a person whose propensity to act out the violent statements was well known by the person to whom the statements were directed. Just because evidence of past acts could possibly be used in an errant fashion, or could well be viewed to be prejudicial, does not mean that the evidence is so unduly prejudicial that it must be kept from the trier of fact regardless of its relevance and materiality. See e.g. United States v. LeMay, 260 F.3d 1018, 1027-1031 (9th Cir. 2001) (upholding the use of prior acts evidence both facially, and as applied, in federal sex offender prosecutions.