Yes , to me the problem with group responsibility is that there are two contrasting pressures. On the one hand the staff member demands to know who did the crime. Fine, but if that person doesn’t own up, and someone else ‘grasses'( ‘dobbing’ in Aus , I believe) him up , certainly in England that ‘grass’ has dishonored not just the students code of behavior, but also , paradoxically , the school’s code of honor as well!!! So you can’t win , and you are being asked to do the unthinkable , with the option of being punished yourself , for abiding by the code.
This paradox is similar to the contrasting ideas that, on the one hand a caning should be extremely painful and the caner looks for evidence it had struck home : whilst on the other hand the public school code required you to maintain a stiff upper lip , or else get extra punishment, plus risk a ragging from your classmates!