Ketubot 27A

הורהנה ⁠— אין, נחבשה ⁠— לא. הוא הדין אפילו נחבשה. ומעשה שהיה, כך היה.

If she was taken as security, in a case where her husband stipulated that if he fails to pay a debt the non-Jews may take his wife and do with her as they please, yes, she requires witnesses to testify that she was not violated. However, if she was imprisoned by the authorities, no, she is deemed untainted even without witnesses. Apparently, the distinction is not based on the dominance of the Jewish people. Rather, it is based on the manner in which she was apprehended. The Talmud answers: The same is true that she is forbidden to her husband even if she was imprisoned, and the reason that the tanna’im testified about a case where she was taken as security is because the incident that transpired, transpired in that manner.

איכא דאמרי, אמר רבא: אף אנן נמי תנינא: העיד רבי יוסי הכהן ורבי זכריה בן הקצב על בת ישראל שהורהנה באשקלון, וריחקוה בני משפחתה, ועדיה מעידים עליה שלא נסתרה ושלא נטמאה, ואמרו חכמים: אם אתם מאמינים שהורהנה ⁠— האמינו שלא נסתרה ושלא נטמאה, ואם אין אתם מאמינים שלא נסתרה ושלא נטמאה ⁠— אל תאמינו שהורהנה.

Some say a different version of this tradition. Rava said that we too learn a proof from a Mishnah for the statement that Rav Shmuel bar Rav Yitzḥak said that Rav said: R' Yosei the priest and R' Zekharya ben HaKatzav testified about a Jewish woman about whom witnesses testified that she was taken as security for a debt in Ashkelon. And the members of her family, who suspected that she had sex there, distanced themselves from her, and her witnesses testified about her that she neither entered into seclusion nor was violated. And the rabbis said to the members of the family: If you believe the witnesses that she was taken as collateral, believe the witnesses who say that she neither entered into seclusion nor was violated. And if you do not believe the witnesses that she neither entered into seclusion nor was violated, do not believe the witnesses that she was taken as collateral at all.