Deep Space Nine was the first show to feature Section 31 and they're still the best to do it, because they understand how it relates to the franchise's moral perspective.
Section 31? For our answer, we’ll have to dig into decades of behind-the-scenes intrigue and centuries of Star Trek ...
In the 1998 Star Trek: Deep Space Nine episode Inquisition, Dr. Julian Bashir (Alexander Siddig) becomes the target of an investigation by Deputy Director Luther Sloan (William Sadler).