Sorry, you're right. I'll now reply directly. I think it depends. If the person in question knows they are guilty of some crime that carries a heavy penalty,

Sorry, you're right. I'll now reply directly. I think it depends. If the person in question knows they are guilty of some crime that carries a heavy penalty, then they may decline the rape kit. If the person in question does not know they are guilty of some crime that carries a heavy penalty, then they likely will not decline a rape kit. I think people who commit crimes cause damage to society, so I tend to have little sympathy for schemes to let them escape justice, FWIW.