I work as a spy for a top secret and ruthless government organisation with a three letter acronym. I know all their dirty secrets and where the skeletons are literally buried. In order to protect myself from being eliminated when I’m no longer required, I’ve downloaded all the organisation’s data and securely encrypted it. I’ve then distributed that encrypted data to friends and reporters.
Is there a technique whereby the data remains encrypted whilst I’m still alive? Clearly I would have to actively take steps to ensure this, and these steps would end upon my disappearance. So whilst I’m alive I do “stuff” perhaps every month, and the shameful secrets remain impossible to decrypt.
I’m aware of secret sharing and key /certificate revocation but not of their flavours. It seems like the very opposite of revoking a public key though. Would I have to keep sending newly encrypted copies out? Is there a cryptographic way to protect myself like this? I’ve read somewhere that Edward Snowdon has such a protective scheme.
Edit: The things I know would bring down the organisation and my friends being reporters, they would publish it as soon as possible. Hence the notion of them not mathematically being able to decrypt unless I'm eliminated. I do not want to rely on their assurances that they won't break the story at the earliest possible opportunity. This allows the organisation to leave me alone.