I asked this along time ago. Every local police department for many years has video cameras recording interviews. Why don't FBI agents have a video deposition for interviews? If they fear the video may get destroyed or they need to preserve the record for decades, they could have video & written documentation.
Why don't they have a transcriber/stenographer recording the deposition? Why are the agents, themselves the only record?
Unless your objective was to change the record to fit your needs.
But of course, it is only the upper echelon. It certainly would never be the rank & file. So we are told.