Performing wuḍūʾ with usurped (ghaṣbī) water, or with water about which it is not known if its owner consents to its use or not, is unlawful and invalid. Furthermore, if wuḍūʾ water drips from one’s face or arms onto a usurped place, or if the place in which one performs wuḍūʾ is usurped, in the event that he cannot perform wuḍūʾ in any other place, his responsibility (taklīf) is to perform tayammum; and if he can perform wuḍūʾ in another place, it is necessary for him to perform wuḍūʾ in that other place. However, in the event that he performs wuḍūʾ in the usurped place, thus committing a sin, his wuḍūʾ is still valid.[46] Ruling 267.* There is no problem in performing wuḍūʾ in the place designated for wuḍūʾ in a school or with water from a school’s pool when one does not know whether the wuḍūʾ place or pool is a charitable endowment (waqf) to the general public or only to the students of the school, as long as people usually perform wuḍūʾ in that place or with water from the pool and no one prohibits them from doing so.