Destruction of evidence charges? I am often surprised at how adaptive the law is for preventing loopholes like this. I would say with great confidence that this wouldn't fly.
How can I destroy evidence if the system was set up before being in custody? And the government preventing you from storing your data with dead man's switch is punishing a thought crime.
I think they would argue you set up the deadman switch with the intention of destroying potentially incriminating information in the future. It's not really any different than setting a flare to burn down your office and destroy filing cabinets of evidence of tax fraud or whatever. That would definitely not fly, arson aspects aside. Just because you set it up before there was any incriminating information doesn't really matter, it is a liability you accept setting it up that it might destroy evidence you are not legally allowed to destroy.
