Building a sukkah without a permit. Sukkah must be removed by 10-9-2015, well after Sukkot is over – just like the old joke.
That said, I've heard (but can't yet confirm) that Jackson Township officials are going door to door in some areas telling people to take down their sukkahs. They're using code violations as the pretext but the real reason likely is the impending hurricane. (However I'm also hearing there are large fines – $2,000 plus $250 for each additional day of violation – being levied in some cases, so this might have more to do with illegally stopping haredi expansion than storm safety.)
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