[Cryptography] What if Responsible Encryption Back-Doors Were Possible?

[Ray Dillinger]

For what it's worth I believe the only "responsible" backdoor suitable
for government use - particularly if it is something that can be
automated - is one that does not allow even one single use of that
backdoor to remain indefinitely secret.

We need a system for accessing the systems of a few dangerous criminals
that allows the government to PROVE at any point that it has not been
invasively scooping absolutely everything that belongs to absolutely
everybody.

In Broad Fuzzy Outlines leaving a million hard details and a hundred
refinements to be designed....

In order to get their backdoor key, perhaps, they have to interact with
a public block chain creating a blinded transaction.  And no valid block
can be created without unblinding the access transactions of blocks that
are turning more than (say) 180 days old.

Because I get the idea that sometimes you have to have covert access for
the sake of a specific investigation, of a specific person for evidence
of a specific crime.  But if that access never becomes known to the
public, or if people CAN use it in the belief that their use of it will
never be known, then it is guaranteed to be abused.

Every morning, political and business reporters (and inevitably gossip
and tabloid reporters) and courtroom attorneys (and inevitably mobsters)
should be waking up, having a healthy breakfast, and consulting the
chain to see the backdoor accesses unmasked this morning.

Every morning, paranoids and tinfoil-hats who irrationally fear the
government (and inevitably mobsters and shysters and spies who have good
cause to fear the government) should be able to reassure themselves by
checking the chain to see whether it reveals today that a while ago
their own data was accessed.

Unmasking shouldn't be required for accesses less than 6 months old, so
that a legitimate law enforcement purpose can be served before the
targets become aware.  But unmasking must become absolutely certain
after some time so that people cannot be deceived about the extent or
nature of the access.

Unmasking a backdoor access should reveal whose data was accessed, who
accessed it, when it was accessed, what specifically they were looking
for, why they had probable cause to believe it was there, and what judge
signed the search warrant.

Even the masked transactions on the chain must be known to exist; Nobody
should ever be able to authorize some program that harvests 330 million
people's data one morning without it becoming known, on the same
morning, that 330 million accesses were made.

				Bear

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