It is a long shot, but:
It could be Inquest of Pilot Pirx, IMDB, from 1979:
In this movie some significant part takes place in the cabin of the spacecraft 'Goliath'. The crew consist of astronauts, humans, and non-humans (called 'nonlinears'). No one knows about others occupation (human or non-human), and so they suspect each other (trying to figure out who is human and who is robot). Some of them report to the captain about possible 'occupation' of the other crew members.
Spaceship pilot Pirx is hired for a mission to test probes to be
placed in the Cassini Division, a gap between rings of Saturn, while
the real secret goal was to evaluate some nonlinears (androids with
"nonlinear" characteristics) for use as crew members on future space
flights. The mission meets with a near disaster and the human crew are
Upon returning to Earth there is an inquest to determine if Pirx was
responsible for the accident. Pirx recounts the events and in the end
it is established that one of the robots caused the malfunction of a
probe and attempted to pass through the Division to launch the probe
manually, an attempt which would kill the human crew members and prove
the superiority of nonlinears over humans.