If the rapist is a legal, green-carded immigrant, it would be interesting to know what due diligence, if any, our government conducted before handing him his immigrant visa. Did they check with the home country's judicial authorities to see if he'd been involved with crime? Child rapists tend to be long time repeat offenders. Does our government do any effective checking of immigrants prior to admitting them?
If the rapist were a US-born U.S. citizen, then it would be interesting to know if rape is more prevalent among some groups, U.S. born or not, and if so, to then debate whether immigration policies that enlarge rape-prone groups are a good idea.
As if a visa somehow magically prevents a visitor from committing a crime.