This episode is made even worse in the DS9 episode, A Man Alone when Odo says that killing one's own clone is still murder. Riker should be in prison for a double homicide.
A Man Alone (episode)

An old enemy of Odo's is murdered behind locked doors, and all the evidence points to Odo as the killer. Doctor Bashir finds Dax playing with an Altonian brain teaser, a puzzle responding to neural theta waves in a holosuite. Eager to get closer to her, he says he loves puzzles and volunteers to play. Before she transfers control to him, she casually mentions that she's been trying to solve it for 140 years. As soon as she transfers control to him, the puzzle bursts in a matter of seconds. Dax t

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