The Way Back implies that Blake has
been getting forged tapes from his brother
and sister, who actually are dead.
Wouldn't the lie, if any, go in the other direction?
At that stage, Blake is a convicted and supposedly
rehabilitated rebel and traitor. Wouldn't The Powers
that Be want him to feel a constant sense of guilt
for getting his family killed (whether or not this
had actually happened) instead of wanting him to
think that his family were still alive off-world?
In the latter case, they *could* serve as hostages
for his continued good behavior, but in the former,
he would be an awe-inspiring example of the high
cost of rebellion and therefore an effective deterrent.
-(Y)