Actually, a multi-employer welfare arrangement ("MEWA") is something you want to avoid, not something you want to strive for. Under ERISA, most employee benefit plans are exempt from most state laws. ERISA provides, however, that a MEWA is subject to state as well as federal law.
However, it appears that you are asking whether it is possible to set up a health benefit plan for a number of governmental employers. The answer is yes, provided that state law allows it. Governmental plans are not subject to the preemption provisions of ERISA in any event, so they must comply with state law whether or not they are MEWAs. However, it is quite common to have a governmental health plan which covers various governmental entities, so long as that plan complies with applicable state and local law.
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