If I remember correctly, it's not complete immunity, but they require a compensation mechanism approved by congress for any issue that doesn't have prior history of being compensated explicitly similar to the situation at hand. It's like 99% immunity.
Right, so federal agents receive absolute immunity by default, and this is guaranteed to continue for every new issue, unless Congress magically becomes un-gridlocked in the meanwhile AND chooses to solve this issue AND chooses to do so every time a new unprecedent issue occurs involving a federal agent.
