That's an insightful question. One rational for this could be that we shouldn't see this in isolation and should also consider other societal aspects too, main

That's an insightful question. One rational for this could be that we shouldn't see this in isolation and should also consider other societal aspects too, mainly - (1) women are perceived as the weaker sex (2) women who commit crimes are actually much lower than male criminals and (3) male pride (men too are held to some unreasonably high standards in society, one of popular ones being that men need to protect women and always be chivalrous towards them). So a male dominated society, while holding a "fallen" woman in contempt, might still irrationally blame themselves for "failing to protect" a woman from going waylaid and thus award her a less harsher punishment to assuage their guilt and as an act to "protect" her from further harm. (This is perhaps why many are now advocating for gender neutral laws because some laws do prescribe different treatment based on the gender of the person involved). Note though that while a judicial punishment might be less severe, the societal contempt that such women face lasts much longer than with a man in a similar situation. Indeed, while, despite the contempt they feel, the judicial system can show restraint due to their legal training to disregard emotions, others in society don't often hold back in showing their disgust and contempt towards a "fallen" women, depending on what gender specific societal standard she has violated. In my own society (in India), I have seen woman who have committed adultery (no longer a crime) being treated more harshly by society than men who have also committed a similar act. From the point of view of our discussion, this could be because the standard ("that woman should display higher level of control over their sexual desire and be more empathetic") is gender specific, and doesn't equally apply to the men for whom the societal standard is different ("men too are expected to control their sexual urges but they can be forgiven as they cannot indulge in it unless a woman consents").