You're free to do whatever you want to your own data (subject to previous judicial order), but the moment a legitimate authority -- whether state or local law enforcement or a Federal agency like Customs and Border Control -- indicates that your data/property is subject to search or review, destroying such data is literal obstruction and will get you as much of a charge as if you flushed evidence away while a cop was asking for it.
If the LEO or agency is overstepping their bounds, once you've been put on notice that you're the subject of an investigation the proper remedy is judicial review and a lawsuit. You don't get to #resist, and you certainly don't get to blow up your phone just because someone taught you this One Weird Trick.
Have fun in jail, bro.