The Torah in Parashat Ki-Teseh (22:29) commands that if a man forced himself upon a Na’ara Betula (virgin girl), he must pay a fine of 50 Kesef to her father, and “Lo Tiheyeh Le’isha” – he must marry her. The Sefer Ha’hinuch explains that the Torah seeks to deter prospective criminals from committing this dreadful act, by requiring a man who does this to marry and support the girl forever. If a person considers perpetrating such a crime, he will realize that afterward, he will be required to marry and support the girl for the rest of his life – in addition to the fine paid to the father – and this will cause him to suppress his evil inclination and desist. The Sefer Ha’hinuch adds that this Misva also ensures that the victim, who was violated and humiliated, and whom men might not want to marry because she had been violated, will be cared for. The Torah commands the man to marry her so that the girl will not have to remain alone, and will have a husband to support her and provide her with her needs.
A general rule is that if the encounter occurred outside the city, where there are no people in the vicinity, then it could be assumed that the man forced himself upon the girl, and nobody was there to help her. If, however, this took place in a city, where the girl could have called for help, then it can be assumed that the relationship was consensual, unless it can be proven otherwise.
The man must marry the girl even if he finds her undesirable, such as if she suffers from some unseemly blemish, or has leprosy. The girl can refuse to marry him, and the father, too, can refuse to allow the man to marry her.
When the man marries the victim, he does not give her a Ketuba. The purpose of the Ketuba document, which requires a husband to pay a large amount to the wife in case of divorce, is to make it difficult for the husband to divorce the wife. In the case of a man who forcefully violated a girl, he is not permitted to divorce her against her will, and so a Ketuba is not necessary.
If a person forcefully violated a girl who is related to him, and thus forbidden to him for marriage, then, quite obviously, he may not marry her. Likewise, if she is not faithful to him, then they must divorce, just as in any case of an adulterous wife.
This Misva is binding upon males, and applies in all places and in all times, though the requirement to pay a fine applies only in the times of the Bet Ha’mikdash, as nowadays, courts are not authorized to impose fines. The requirement to marry the girl if she so desires, however, applies even today.