To Save a Life invokes the following laws:
1. To ensure that the common folk would not fear endeavoring saving a third party in mortal distress, the sages instituted a special dispensation from paying for collateral damages the savior may cause en route to saving a victim's life [Maseches Bava Kama 117b, Choshen Mishpat 380: 3]. (See further issues as per the liabilities of a paid practitioner, and one saving him/herself; both of whom do not generally need an additional incentive to involve themselves in the rescue efforts.)
2. Though R' Yaakov ben Yaakov Moshe Lorberbaum of Lissa (1760-1832) in his Nesivos Hamishpat (340: 6) understands this collateral liability dispensation to incorporate liabilities stemming from contractual law (i.e. borrowing ammunition to protect a third party from an offender and losing it during the clash), as well as from collateral damages; Rav Moshe Feinstein dictated unequivocally that the Talmud's dispensation is restricted to collateral damages [Igros Moshe C.M. II 63]. Any liabilities incurred during the rescue efforts resulting from theft, contractual (i.e. loans) or property (bailment's, or shmira) law remains in effect.
Application:
R. Feinstein ruled that R. Halberstam determination to pay his creditors was not an act of piety. but in-fact was required by law, regardless of his original humanitarian motives.
Mrs. Rhine damaged the medicine cabinet and chair. As she was endeavoring to save Aaron's life, she is absolved.
Theoretically, in-line with R. Feinstein's verdict, she would be have been required to repay the host school for using the epi-pen, if not for the fact that the epi-pen was obviously earmarked for such usage.
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