I wonder if the Enterprise
computer would track the Klingon visitors. Would Duras' movements aboard the ship reveal that he
was the last person in K'Ehleyr's quarters prior to Worf finding her?
At any rate, Klingon
justice is swift. Even Duras' men didn't object to Worf killing him, when Worf said that K'Ehleyr was his mate. They just let him go back to his ship after the duel.
Still, as far as the Federation is concerned, the murder of K'Ehleyr would have to be resolved. But no further mention is made of it. It's as though they accept that Duras must
have been the killer. Perhaps the Klingons - or at least, Duras' men - admitted
that Duras killed her, and with him dead, no further action on the part of the Federation was possible or necessary.