In other words, I think in Starfleet's eyes if you needed a JAG officer following all your captains around, then you haven't promoted people trustworthy enough with the level of confidence to handle PD discretion situations to the rank of captain.
Data, an android who should know what to do answers a primitive Call as a Lt. Commander, as an Ensign, Harry Kim knew even after only 4 years of experience that you don't answer. Was an investigation launched into Data's initial screw up, nope, Picard was allowed to ignore it and use continuing transmissions, which likely wouldn't have happened in the way they did had it not been for Data's violation of the PD, to justify interfering.
Crusher was allowed to beam up wounded primitives even though they were unsure how they would react to her memory wipe, had these people have been left they would have died, it would have been unfortunate but it would not have led to the creation of a religion and kidnapping of Federation citizens along with the assault of a senior officer. Once again was there any kind of investigation into why they were beamed up in the first place, nope, they just went along on their merry way.
Worf, who seems to love violating the Directive kills a Klingon leadership contender, thus changing the course of history for not only the Klingons but virtually every Species in the Alpha/Beta neighborhood at least. A few years later he decided he didn't like the crazed dictator he installed with the previous action then kills him and installs a new leader, I know they say the perfect form of Government is Democracy tempered with Assassination but this is ridiculous. Does this effect his career in any way? Not really, granted it took a while to make Lt. Commander these issues are never brought up again or investigated in any meaningful way, in one case he is given a lecture from Picard, boy that fits the crime, and on the other everyone seems to congratulate him.
It is hard to believe that each of these can be justified by 'changing situations', particularly the first one regarding Data.
Of course the most prevalent of them all, the crew of the USS Voyager who seemed to feel it was their personal duty to break every rule, regulation and law in the Federation/Starfleet. And what do we do to this Captain when she returns, surely we investigate her actions, throw her out of the Fleet, toss her in the Brig, give a stern talking to by Picard? Nope we promote her, seemingly bypassing a Rank on the way, and post her to a position of authority over the other big offender, the Crew of the Enterprise, a fitting end to the Prime Directive as we know it...
There may be times when we are powerless to prevent injustice, but there must never be a time when we fail to protest.
Dreaming in Color Living in Black and White, Sitting in a Grey Day Leaning on a Bright New Tomorrow.
-Billy Ray Cyrus