[MeetingsBrowser]

So you would like people to feel comfortable telling the whole truth, unless it’s something really important?

[dehrmann]

Secret witnesses aren't allowed to testify in the US. Not that these were court trials.

[lazide]

Except for FISA.

And don’t forget that cases ‘pertaining to national security’ get thrown out all the time. [https://www.fjc.gov/content/overview-7]

Either because key evidence is classified, or witnesses are, or testimony would be considered a threat to national security, etc.