The witnesses were men who had been trained since birn to tell the truth and remember everything they saw. Any Help

Book? Short story? YA book? Spy novel? You'll have to give me more than what you did. You want to know the name of the author?

We remember 1 or more stories/books with the described characters. The author would be in the time/class of Bradbury, Heinlein, etc

"We"?

You are looking for either a book or a short story (or more than one?? ) about witnesses, and the author is similar to Bradbury or Heinlein? Any more information about what is in the story? Setting? Other characters? Time? Characters' names?