Shomer

A shomer (Hebrew: שומר‎‎, pl. שומרים, shomrim) in Halacha is a Jewish legal guardian, entrusted with the custody and care of another's object.

The laws of shomrim are derived from the Torah in Shemot (Exodus) . It is discussed in the Talmud in Seder Nezikin in tractates Bava Kamma and Bava Metzia.

There are four types of shomrim: shomer ḥinnam, shomer sakhar, shoel, and sokher, corresponding to an unpaid custodian, a paid custodian, a borrower, and a renter respectively. Each shomer has specific distinct laws that apply to it. In halacha there are two major factors that determine a guardian's liability: the ability to use the item, and the exchange of money. In general the ability to use the item (in the case of a renter and a borrower) or being paid to watch the item (in the case of the paid watchman) increases the guardian's liability, while paying for use of the item (i.e. a renter) decreases the guardian's liability.

A shomer Chinam (Hebrew: שומר חנם, pl. שומרי חנם, shomrei chinam), or unpaid watchman, is one who watches an item without receiving payment for his watching. Shomrei cḥinnam are liable only for damages that result from their own negligence. They must pay for damages that result from their negligence.

The shomer cḥinnam does not have permission to use the item he or she is entrusted with.

A shomer sakhar (Hebrew: שומר שכר, pl. שומרי שכר, shomrei sakhar), or paid watchman, also known as a noseh sakhar (Hebrew: נושא שכר, one who receives payment) is one who watches an item in exchange for compensation. In addition to the obligations of the shomer ḥinnam, shomrei sakhar are liable if the item is stolen. Armed robbery is exempted from this responsibility, however, as it is considered beyond the custodian's reasonable control.

Shomrei shakhar are also liable if the item is lost or misplaced, even if the loss was not a result of negligence.

In addition to the paid watchman's heightened level of liability, in certain ways the shomer sakhar is expected to perform a higher level of custodianship. A shomer sakhar, for example, cannot watch an item in a way that would only protect it from a reasonable wind, but rather must watch an item in a way as to protect it from any possible wind, and the absence of such would make the shomer liable.

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