Bava Metzia 97B

בשעה שהיתה שאולה מתה. והלה אומר: איני יודע ⁠– חייב.

or: It died during the period in which it was being borrowed, so that, according to his claim, the borrower is liable to pay for the cow, and the other one, the borrower, says: I do not know what happened, the borrower is liable to pay.

השוכר אומר: שכורה מתה, ביום שהיתה שכורה מתה, בשעה שהיתה שכורה מתה. והלה אומר: איני יודע ⁠– פטור.

If the renter says: The rented cow is the one that died; or: It died on the day that it was being rented; or: It died during the period in which it was being rented, and the other one, the owner of the cow, says: I do not know what happened, the renter is exempt.

זה אומר: שאולה, וזה אומר: שכורה ⁠– ישבע השוכר ששכורה מתה.

If this owner says with certitude: The borrowed cow is the one that died, and that renter says with certitude: The rented cow is the one that died, then the renter takes an oath that the rented cow is the one that died, and he is then exempt from liability.

זה אומר: איני יודע, וזה אומר: איני יודע ⁠– יחלוקו.

If this one says: I do not know what happened, and that one says: I do not know what happened, then they divide the disputed amount. The bailee is liable to pay for only half the value of the cow.

גמ׳ שמעת מינה: מנה לי בידך, והלה אומר: איני יודע ⁠– חייב.

Talmud: Conclude from the Mishnah that in a comparable situation, where one says to another: I have 100 dinars in your possession, and the other one says: I do not know whether or not I have your money, that the defendant is liable to pay.