Here as in Shannon there are indications that the defendant was in fact guilty of forcible rape, which is indisputably a crime of violence, but the indications do not appear in the charging document, so we are barred from considering them. In light of these legal and sociological facts, it is difficult to maintain on a priori grounds that sex is physically dangerous to 16 year old girls. This may be wrong, but a 15-year sentence enhancement ought not to turn on sheer conjecture. We have left out of consideration so far the age of the statutory rapist. In Shannon he was only 17.
Most states recognize that a substantial age difference is an aggravating factor.
The primary concern is that the older male will use deceptive or manipulative methods to overcome the immature female's reluctance to engage in sex. In addition, intercourse with an older male involves an enhanced risk of sexually transmitted disease because an adult man is more likely to be infected than a teenager. And there is evidence that a 16 year old girl is at greater risk of physical injury, in the event that she becomes pregnant, than if she were older, mainly because she is less likely to obtain good prenatal care. This evidence is not inconsistent with Illinois' permitting marriage at 16, since the requirement of parental consent provides some protection for the immature 16 year old. The difficulty with using this evidence as a basis for classifying Thomas's crime as a crime of violence is that it requires an essentially legislative judgment in a field in which the responsibility for making such judgments rests with Congress and the U.S. Sentencing Commission.