Podesta's immunity is only in reference to select crimes and is not all-encompassing.
How do you legally inject evidence?
When Podesta testifies it will not only implicate Manafort but at least a dozen others. Those indictments will then have sufficient support to become actionable. The guaranteed immunity is only if he tells the truth and the whole truth, otherwise, it becomes invalid.
The "Podesta to testify against Manafort" headlines are to keep the show going and not to spook specific bad actors.
Screencap this post.
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