Star Trek: 10 Times Starfleet Officers Crossed The Line

4. Miles O'Brien Warns Bilby - Honor Among Thieves

Honor Among Thieves gave a then-rare glance at the Orion Syndicate, the feared crime empire that dominated the underworld of the Alpha Quadrant. Miles O'Brien, recruited for his technical skills as much as his ability to blend into a bar, is sent by Starfleet Intelligence to Farius Prime, tasked with infiltrating the Syndicate.

After befriending a member named Bilby, O'Brien (posing as a man named Connelly) is horrified to learn that the Syndicate is doing business with the Dominion. Bilby is assigned a special mission: use Klingon disruptors (repaired by O'Brien) to assassinate the Klingon ambassador to Farius. This, the Dominion hopes, will look like a political killing, as said ambassador is strongly against the Klingon-Federation alliance.

O'Brien does his duty and passes this information back to his handler, only to have a change of heart. For Bilby, it's a suicide mission, though the man doesn't know it. O'Brien, having grown sympathetic to Bilby's position, warns him, though it has little impact - the man is dead either way, for the Syndicate will kill him, and his family, if he tries to run.

Chadwick, O'Brien's handler, is the only reason the non-com officer is able to return to Deep Space Nine, as he opts not to report his actions to Starfleet, understanding that emotion took control of the day. O'Brien, lucky in a certain respect, keeps his position and inherits Bilby's cat, Chester, as well.