The source added that the investigation proved that the bases of the genocide crime "were completed with a series of illegal arrests followed in some cases with assassinations or cases of disappearances and were preceded, according to information attached to the file, by cases of torture."
The investigation found that people were clearly not treated fairly.
People was tortured and assassinated, so they were not treated fairly. The fairness of the killings is not mention on the text but it is implicit to being killed.
( z1 find :ARG0 ( z2 investigate ) :ARG1 ( z3 treat :polarity - :ARG1 ( z4 person ) :ARG1-of ( z5 fair ) :ARG1-of ( z6 clear ) ) )