Would it be possible to combine rophynol and methamphetamine to give somebody an erection and involve them in intercourse they would have no memory of?

Legal question: This is as much a legal question as a clinical one. I would suggest if there is concern that someone was given a sedative hypnotic benzodiazepine such as flunitrazepam (rohypnol) and methamphetamine (an illegal substance), you should call the police. It is hard to say if this is possible clinically, but it did occur it would likely be considered sexual assault.