a friend of mine is travelling to the usa soon and he is worried sick that a drug related crime will stop him and make him be deported on arrival.. (it was in the uk) this crime was 12 years ago and we are lead to believe that the database was computerized 10 years ago...if this is the case will there be a chance his name wont show up should the arrivals department check his name?
go in on the visa waver scheme (the one one you fill in on the plane) and shouldn't be a problem. US customs do NOT have access to the UK criminal database for those reasons so there is no reason they should know about it at all.
if it is only for a visit/holiday then no problem, if trying to get a green card to work or similar then yes it will go against them and probably stop them getting in.
I think it is a duty of America to make all efforts possible to ensure that no people involved in drugs, guns, or organized crime get into their country and ruin its pristine condition.