It was hard.
Space combat was easier. :) lol.
This one was so (excitedly: Journey to Babel) C.S.I.
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This was my response (top of page 5)
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Checking the video logs is prudent for sure.
If no good video, was there good audio? Compare voice patterns and all audio gathered.
How was the person attacked? From range or melee assault? If from a distance, do you know where it came from? Determine trajectory with lasers or if location unknown use audio data and location environmental readings to determine sources of attack. If location is found, does it reveal any clues at point of origin? Scan point of origin with tricorder and for physical evidence.
What type of weapon was used? Can it be determined by above findings? Was it a common or hard to get item? Who would have access to that kind of weapon?
As someone stated already I think, comparing times & loctations of people at time of attack. Rebuild scenario in the holodeck-suite? Look at the scene from different angles. Study every persons actions and facial expressions at the time of attack (hard reading Vulcans but it could probably be done).
If a melee attack, scan victim with science and medical tricorder for anything unusual or for any D.N.A.
Use non-invasive scanning and look for traces of residual high energy on the crew and guests when possible as fast as possible.
(already stated) Put a security detail on the ambassadors.
Hypnotize any of your crew that were there and try to see if any data was imprinted they are unaware of. Or attempt to recovery memory data of the event and generate visualizations for that persons point of vie on a screen or in a holodeck/suite.
Follow the money.
Ask the ambassadors and delegates what the consequences would be if the trades were to fail?
As someone pointed out: Mind meld with the person attacked and see what you can from their perspective?
The victim gets a lie detector test. Was the attack faked?
Ask the computer to attempt to determine probable attacker based on compiled evidence from above?
Talk to the bartender (they know everything).
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added this later:
It was Colonel Mustard (Thelev) the Orion, disguised as an Andorian with the transmitter/receiver hidden in his fake antenna...
...in the pantry?
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From Memory Alpha:
Quote:
When Kirk orders McCoy to perform an autopsy on Thelev to determine his true identity, Spock surmises Thelev and the attackers in the enemy ship were Orions, who had much to gain from disrupting the Babel conference so they could continue to loot Coridan of its dilithium.
http://memory-alpha.org/en/wiki/Jour...sode)#Act_Four