Investigation
An investigation was the  or examination of facts to establish the truth of an event. This was typically conducted by an investigator.

In approximately 3074, The Doctor's EMH backup module told  that he would not cooperate with his investigation into the  if Quarren didn't stop treating him like a second-class hologram. ()

See also 
 Criminal Investigations
 Department of Investigation
 Department of Temporal Investigations
 Director of Investigations
 Federal Bureau of Investigation

External link 
 

Law
Science