(written from a Production point of view)
Mark Eugene O'Connell, formerly known as Mark Gehred-O'Connell, is a writer who contributed stories and also wrote teleplays for four episodes of Star Trek: Deep Space Nine. He wrote both the story and teleplay (with Ira Steven Behr and Robert Hewitt Wolfe) for the second season episode "Second Sight". Gehred-O'Connell previously contributed the original storyline to the Star Trek: The Next Generation sixth season episode "Timescape".
Gehred-O'Connell was inspired to write "For the Cause" by the Oklahoma Bombings. He said he was surprised that many Americans thought that they had been committed by a foreigner, when in fact the culprit was the home grown white supremacist Timothy McVeigh. This premise was diluted in the episode but as he says, in the case of an attack on Deep Space 9, "who would they immediately suspect? What if it turned out to be the last person in the world to come to mind? I just wanted to play with that idea. And it ended up being a story where Kasidy Yates turns out to be the number-one suspect." (Star Trek: Deep Space Nine Companion (p. 339))
Gehred-O'Connell is the author of The Close Encounters Man. An article promoting the book mentioned that "Who Mourns for Morn?" was a fan favorite. 
Star Trek credits
- TNG: "Timescape" – Original Storyline (uncredited)