Hrm - I'll have a go at being less vague. By actions met by general criticism and can't be justified I meant actions that would both be met with criticism and,

Hrm - I'll have a go at being less vague. By actions met by general criticism and can't be justified I meant actions that would both be met with criticism and, given enough surrounding information, wouldn't remove the majority of criticism. National security positions will need to execute actions that are pretty opaque and distasteful to the general public but, with that additional information in hand, would be reasonable to most people. So arresting some fellow who looks like a family man but was actually organizing an attack would be generally criticized but justifiable - on the other hand most forms of torture tend to be ineffective at information gathering and cause excessive pain and suffering and are less justifiable. For politicians I'm going to guess that a lot of stuff they don't want on record is specifically related to their self-betterment by somehow (even minorly) compromising their duty.