As the sinking of a boat and the accidental death of a crew member have little to do with the effectiveness of torture, I can only conclude that you wish to partake in a bout of gratuitous French bashing.

In this case, I suggest that you start by getting some better material. The Rainbow Warrior is just a blip on the radar. You will find better attack angles in our post-WWII colonial behaviour (for instance, the repression in Algeria and Madagascar), our colonial wars or our African policy. Godspeed.