More often than not, people who said their drinks were spiked had quite simply drank too much. Evans might have a vile view of women but it is a bit far fetched that he would rohypnol the girl.
Even if he does wangle his way out of this on appeal, the simple fact is he took advantage of a girl who would have been quite clearly off her face and was in no fit state to give consent. Either way, that makes him an arsehole in my opinion.