You can have official legal findings whenever the system says you can have official legal findings. One option would be to close the loop and have the system prosecute itself (plenty of precedent). There are others.
Reinforcing the reliability of the system directly reinforces the legitimacy of the state's monopoly on violence - and that's an exceedingly big deal. Perhaps the cost-benefit analysis doesn't fall out in that direction, but I'm wary of that idea without a lot of evidence to back it up.
I think the state's own findings are quite sufficient. The trick is to incentivize their use without unduly obstructing other operations of equal importance.
The state has already satisfied itself sufficiently to reverse a murder conviction. If the investigation that led to that course of action was causally descended from an article written by a journalist - what of it?
If you believe that the actions taken by the state up to this point were unwarranted, say so explicitly. Otherwise, please recognize that I am not talking about journalists here.