If a "potato block" is applied to a student one night, and the professor expels the military commissar, the message about the military commissar's expulsion will not appear in the newspaper. (This is done to avoid revealing the military commissar's role to others.)
I don't understand the point... why is it so important not to reveal the role of an already killed military commissar?
When a student is expelled, they automatically join the army. When a military commissar is killed, the player joins the army and dies there.