The Yerushalmi[1] states that shuls and batei midrash require bedikat chametz because various meals are held in them. The Tur[2] says that the shuls of his time required bedika because small children would bring food inside. Major Acharonim[3] stipulate that this bedika should be carried out in accordance with the rules of bedikat chametz, such as doing it on the night of the 14th of Nisan by candlelight. The Shulchan Aruch HaRav[4] and Mishna Berura[5] complain that shamashim[6] are not sufficiently careful to do this bedika specifically on the 14th at night.
Let us take a more thorough look at the reason for this particular bedika. To begin with, there is a machloket among Rishonim why bedikat chametz is required in general. Rashi[7] says that it is in order to avoid the Torah’s prohibition of bal yeira’eh ubal yimatzei (not to possess chametz in one’s domain on Pesach). In contrast, Tosafot[8] says that the Rabbis instituted bedikat chametz to distance people from the possibility of eating chametz.
It is unclear whether the first reason applies to chametz that might have been left behind in a shul. The Chidushei Hagahot[9] maintains that were it not for the precedent of the Yerushalmi, we would say there is no need for bedika in shul; bal yeira’eh ubal yimatzei cannot apply to a public place, as it is not the domain of any individual. The Perisha[10] says that we would have posited that bal yeira’eh bal yimatzei and bedika do not apply because whatever is left in a shul becomes hefker (rendered ownerless). He points out that the Yerushalmi assumes that we are more stringent regarding shuls than the regular rules would indicate. The Da’at Torah[11] conjectures that the problem is that the members of the community become partners in whatever is left in shul, and partners can violate bal yeira’eh ubal yimatzei in their joint possession of chametz. However, he questions whether there is much of a chance that a significant amount of chametz would be present (a k’zayit[12] per person), which would justify requiring bedikat chametz.
The Aruch HaShulchan[13] presumes that since bal yeira’eh ubal yimatzei, which is likely the main reason for bedikat chametz, does not apply in a shul, one should not make a beracha before the bedika. The Shulchan Aruch HaRav[14] and Mishna Berura[15] disagree and maintain that a beracha is called for. Many others suggest that to avoid the doubt of saying a beracha l’vatala,[16] the designee for the bedika in shul should check his house first and then proceed directly to check the shul, all based on the original beracha. The travel time is not a hefsek (break) regarding the beracha.[17]
There are opinions that bedikat chametz in a shul is not a public obligation per se, but that we are concerned that whoever might have left chametz behind (including the fathers of the young children mentioned above) would violate bal yeira’eh ubal yimatzei. The shamash has an obligation to look out for those members of the congregation who may unknowingly be in that situation. In any case, whoever else is willing to lend a hand may search with a beracha on behalf of unspecified others.[18]
Based on the above presentation, it is logical that bedikat chametz in a shul is an exception to the regular rules. Therefore, one could advance the claim that there is no similar obligation to do a formal bedika in other public facilities. However, we do note that Rav Ovadia Yosef takes for granted that public institutions such as bus companies and airlines should check their relevant equipment for chametz.[19]