The Third Circuit, in Caldwell has issued a lengthy opinion which clearly explains Federal Rules of Evidence 403 and 404(b) and the law regarding the introduction of evidence of prior convictions in a federal criminal trial. Caldwell was convicted in the trial court of being a felon in possession of a firearm. As trial, the government sought to introduce Caldwell’s prior conviction of being a felon in possession of a gun. And the District Court judge, surprisingly, let the prior conviction in. Caldwell appealed his conviction on the grounds that the District Court judge erred in admitting the prior conviction. Fed. R. Evid. 404(b)(1) provides that “[e]vidence of a crime, wrong, or other act is not admissible to prove a person's character in order to show that on a particular occasion the person acted in accordance with the character.” But in limited circumstances, it can be introduced to prove other elements of the offense—for example, to prove knowledge, intent or modis operendi (similar means of committing crime). Here, the prior conviction was admitted to prove knowledge, what under certain circumstances could be a valid purpose. However, based on the facts of this case, knowledge was not an issue because the issue here was actual possession. The government’s claim was that Caldwell was physically holding a gun in his hand. If the government’s claim was true and Caldwell was in fact holding a gun, Caldwell would have obviously known he was holding the gun. Therefore, his “knowledge” was irrelevant. If, however, their claim was that Caldwell was holding a bag which had a gun in it, then knowledge might be an issue (i.e. did Caldwell know the bag contained a gun?). The Third Circuit held that since this evidence was, therefore, improperly admitted under Fed. R. Evid. 404(b), the court need not reach a balancing test under Fed. R. Evid 403 as to whether the probative value outweighed the prejudice. The government also argued in the lower court that Caldwell put his knowledge “at issue” by claiming innocence. The lower court ruled that once a defendant claims they are innocent, prior convictions are admissible to show they “knew” they were guilty. Confused at how the District Court reached such an obviously wrong conclusion “despite starting in the right direction,” the Third Circuit vacated Caldwell’s conviction. Thankfully, the Third Circuit reached this important decision in Caldwell. About Hope Lefeber: Hope Lefeber is a federal criminal defense attorney in Philadelphia. With over 30 years experience, she is recognized by Superlawyers and is ranked by the National Trial Lawyers as one of the top 100 Criminal Defense Lawyers in the United States. Ms. Lefeber’s key areas of practice include defense in business and corporate fraud, mail and wire fraud, money laundering, tax fraud and other white collar crimes, conspiracy and drug offenses.