Part III : Captivity #Section V : Relations between prisoners of war and the authorities #Chapter 1 : Complaints of prisoners of war respecting the conditions of captivity - Art. 42.
Art. 42. Prisoners of war shall have the right to bring to the notice of the military authorities, in whose hands they are, their petitions concerning the conditions of captivity to which they are subjected.
They shall also have the right to communicate with the representatives of the protecting Powers in order to draw their attention to the points on which they have complaints to make with regard to the conditions of captivity.
Such petitions and complaints shall be transmitted immediately.
Even though they are found to be groundless, they shall not give rise to any punishment.