To continue the brainstorming... Maybe this could be done with some kind of "live tagging" during race for each car? I mean every car have some kind of "cache" with easy tags like "accelerating" "braking" "out of track", etc. These tags are created live, for example if the player is accelerating the car have the tag "accelerating" these tags could be used in conjunction of this "aura" to determine if the car is doing wrong due in that part of the track you should be bracking not accelerating. Of course in that part of the track the track itself have "areas" to determine the weight of the tagging. On a 180 degrees turn you should be decelerating or accelerating? So the weight will be more heavy if a car have the tag "braking" on its cache against another car that have the tag "acceleating". So the penalized car in that part of the circuit will be the one that have the tag accelerating, not the one that have the tag braking... Another example: if a car have the tag "out of track" and "accelerating" and some kind of tag that registers the angle that the car have in relation of the track, and reenters to the circuit these could be used to give that car a "unsafe re-join" penalty. Do I explain myself? Nice brick I wrote... As I told pure brainstorming I have no idea of programming...
Yes, you explained yourself. Sounds good to me generally speaking. I'm afraid doing this the 'easy' way programming wise would need a lot of testing and adapting the zones per car and track and doing it the more refined way could be extremely resource heavy on both development and CPU or servers. But again, a nice idea. Car was off track a second before the contact + car's angle to the racing line was more than 15° = unsafe rejoin.
I don't know why your whole focus is on technical stuff like "auras" or "tags". These can only be useful when you already have good enough rules, expressed in human language, to determine who's wrong and now need to put it in code. So far the only two rules you came up with is "if the car behind is accelerating where you need to be braking" and "if the car was accelerating while off-track before it hit another car". It looks like you're dismissing this stuff as if it's easy to do once tags and auras are in place, but no, it's literally the core of the issue, it's what makes this task so complex that no one came up with anything that's above "eh, okay, at least it's better than nothing". Not only you need to come up with all these rules, you also need to take care of the majority of fringe cases for each of them. However, I believe we don't need to go "all or nothing" here, even a couple rules, if they work consistently, will improve the quality of the system. So far, only the unsafe rejoin seems to be simple enough to implement.
Unsafe rejoins and intentional wrecks in corners are the most annoying cases in my eyes. Solving those with an easy solution would fit into the Pareto principle (80/20-rule). It's clear that all of those smaller collisions, where since the start of time stewards have struggled coming to a good decision for, can't be handled with a code-based system. You won't be able to detect moving under braking and similar cases, you're absolutely right there.
Human knowledge of the rules includes a lot of general understanding, subjectivity and what "feels right", something that computers don't have. Unless we're going to try and teach an AI how to do stewarding, for every sportsmanship rule we need a set of very strictly laid out conditions for what's okay and what's not okay, in meters, degrees, seconds, etc.