Imagine a convict who was blackmailed into confessing to a crime (this blackmail happens prior to the crime). Not only that, they were also blackmailed into doing certain incriminating actions, such as e.g. transporting the corpse to a place, leaving it there, and being seen on CCTV footage leaving the area.
Now, after the convict has been convicted, if the video of the blackmail, along with the blackmail material, is published, can this ever be good enough to exonerate the convict, given that the convict also retracts their confession after the release?
If such a release would be sufficient (which I assume it would be in certain cases), my question is then the following:
When would it be sufficient? How weak would the evidence that the convict committed the crime have to be for this release to be sufficient on its own?
In certain cases, I guess the evidence could be strong enough that the release of the proof of blackmail wouldn't be good enough. Perhaps this is only true in cases where the evidence was sufficiently good that all confessions were superfluous to the proof of guilt?
Furthermore, a question of what even constitutes as "proof of blackmail" arises. I am simply imagining a video of the blackmailer telling the convict that they have to do "X" in order for "Y" not to be released. And then this video is released in conjunction with Y. Furthermore, if Y is undeniable proof that the convict did something of a nature far more grave and criminal than the crime they confessed to, this makes it very unlikely that the whole ordeal is a tactic to exonerate the convict, given that it would only put the convict in more legal and social trouble than their original conviction.