That's a very good question. Silva-Trevino explicitly deals with analyzing crimes involving moral turpitude, and not aggravated felonies. I have heard though of ICE attorneys trying to apply Silva-Trevino to aggravated felony charges. Moreover, other cases, like Matter of Babaisakov, 24 I&N Dec. 306 (BIA 2007), http://www.usdoj.gov/eoir/vll/intdec/vol24/3585.pdf and Nijawhan v. Holder, 129 S.Ct. 2294 (2009) http://www.supremecourtus.gov/opinions/08pdf/08-495.pdf, permit the trier of fact to go beyond the record of conviction in certain limited circumstances. For example, Nijhawan permits review of extra-record evidence for state offenses charged under INA s. 101(a)(43)(M)(i) (fraud in excess of $10,000), as the language of the aggravated felony provisions offense invites a "circumstance-specific" approach, rather than a categorical one. We'll see how far the courts are willing to stretch this doctrine.