you do not think that would be ann kuster usually vague? >> if the jury were asked to decide whether that present a substantial risk beyond reasonable doubt, i don't think that would cause the same problems, your honor. the other thing that is inherent in these definitions is when it requires to be -- the question to be an element of the defense, you only need to look at the elements of that predicate offense to determine whether it qualifies. >> congress was trying to do something here. it's a legitimate thing to do. to impose an enhanced penalty for people who are felons who possess firearms and have a record of prior convictions for certain category of offenses. if the residual clause is held to be unconstitutionally vague is there any other way the congress can a college that end? >> there is. one solution would be to tie the risk to the elements. you can keep the same 14 words but add in has an element that pre-creation of serious potential risk and anything that did not fall within that congress could add an offense. litigants of defe