The account at Deuteronomy 22:25-27 is not primarily about proving the man’s guilt, because that was acknowledged. This law focused on establishing the woman’s innocence. Note the context.

The preceding verses speak of a man who had sex with an engaged woman “in the city.” In doing that, he was guilty of adultery, since the engaged woman was viewed as married. What about the woman? “She did not scream in the city.” If she had done so, others would certainly have heard her and would have defended her. But she did not scream. Thus, she was sharing in the adultery, so both were judged guilty.​—Deut. 22:23, 24.

The Law next outlined a different situation: “If, however, the man happened to meet the engaged girl in the field and the man overpowered her and lay down with her, the man who lay down with her is to die by himself, and you must do nothing to the girl. The girl has not committed a sin deserving of death. This case is the same as when a man attacks his fellow man and murders him. For he happened to meet her in the field, and the engaged girl screamed, but there was no one to rescue her.”​—Deut. 22:25-27.

In that case, the woman was given the benefit of the doubt. In what sense? It was assumed that she “screamed, but there was no one to rescue her.” So she was not committing adultery. The man, however, was guilty of rape and adultery because he “overpowered her and lay down with her,” the engaged woman.

Hence, even though this law focused on the woman’s innocence, the account rightly described the man as guilty of rape and adultery. We can be confident that the judges would “investigate the matter thoroughly” and render a decision in line with the standard that God had set out plainly and repeatedly.​—Deut. 13:14; 17:4; Ex. 20:14.